Thanksgiving day is a time when we have a chance to get together with friends and family and be thankful for the gifts we have received, both tangible and intangible, throughout the year.
The day before Thanksgiving is the busiest travel day of the year, and since many people fly themselves to spend time with family and friends on trips they wouldn't have been able to fit into a busy schedule otherwise, we should be grateful for the wonder of flight. To that end, check out this Bloom County from 1984 where Opus gives his rendition of John Gillespie Magee Junior's "High Flight" and appreciate that pilots can do something that a penguin can't.
Thank you, readers, for making another year of Keyboard and Rudder worthwhile. The best of the holiday to you and yours.
Thursday, November 28, 2013
Thursday, November 21, 2013
How does a plane land at the wrong airport?
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A good friend sent me a story from CNN about a 747 that landed at the wrong airport last night and asked how it could happen. The short answer is that it's not as hard as it seems, especially under the circumstances.
For a while now, when teaching about situational awareness, I have used the example of this C-17 Globemaster crew that landed at Peter O. Knight airport in Tampa instead of MacDill Air Force Base where they had intended:
Thanks to the 747 crew, I have a second example of how easy it is to chase the wrong patch of concrete. Keep in mind that both of these examples happened to professional crews using modern equipment and avionics. (Update: USA today has a short rundown of how many times this has happened in just the last 10 years.)
When I started to read the story my friend sent me, I originally thought, "Oh, they must have landed at Mid-Continent instead thinking it was McConnell AFB. Both of them have long parallel runways heading in the same direction." I've been to Mid-Continent (center-left underneath the "WICHITA" below) and I remember when I was looking at the sectional chart during my flight planning I made a mental note as to how much McConnell looks like Mid-Continent and to double-check I was pointed at the right one once I got there.
Both of these incidents had several things in common:
Tower controllers have lots of other things they're doing at the same time. The usual depiction of controllers as people staring at a radar screen unblinkingly with nothing else in front of them is only true of either center controllers or approach controllers. You've seen these time after time, including in the funny but underappreciated movie Pushing Tin with John Cusack, Billy Bob Thornton, and Angelina Jolie:
That stereotypical image isn't even remotely true of tower controllers because their job isn't to get aircraft from Point A to Point B. The aircraft has already made it almost to Point B and their job is to sequence them in line with other aircraft that may already be landing (or waiting to take off), and it's up to the pilot to actually land it. They might notice if the aircraft's blip (called a data block) drops off the radar early, but in this case they were in an area where radar coverage goes all the way to the ground (as the dotted magenta line surrounding AAO, the airport the 747 crew landed at, shows above). If the aircraft is in distress or the pilot tells the tower controller on initial contact that they're a student pilot, the controller will watch the display very closely, but for a routine flight flown by a highly experienced crew (no one just hops into one of the front seats of a 747 without thousands and thousands of hours) in the middle of the night with no other traffic around, its very easy to see why this wouldn't be noticed. After all, controllers can't fly the airplane, and they expect the people who are to do the job right.
Regarding (2), the only thing that surprised me about the C-17 in Tampa is that it hadn't happened even earlier or more often. Peter O. Knight looks much like a miniature version of MacDill, and it is directly in line for final with one of MacDill's runways. This is very similar to an environment the 747 crew was put in, as you can see by this sectional chart excerpt:
In the Wichita chart excerpt above, I drew a cyan line connecting the two to emphasize how both runways go in the same direction and line up with the flight path of the 747 almost perfectly. At any time, but especially at night, these airports wouldn't look all that different from one another. Since I don't have the time to hop in the plane and fly the 700+ miles to take a good, real picture, here's a view of what the arrangement looks like at night in Microsoft Flight Simulator X from an altitude and distance they were likely to be at:
There's the airport they landed at, from 4,000 feet and 10 miles out, which is my best educated guess at where they were. (Update 11/22: I dug up the flight's track log on FlightAware and that was one outstanding guess. That's pretty close to where they were at one point.) Did you notice the darker patch in the background? Yeah, they probably didn't either. That's because they were in the right vicinity, the heading was about right, the altitude was about right, and there was an airport right about where one should be. With that in mind, once the pilot flying saw the airport, his mind locked on to it and he concentrated only on flying safely down to it. Once the airport is in sight, even GPS or the FMS gets ignored, because the point of navigation systems is to get you to the point where you have the airport in sight.
The concentration required on approach forces the mind into a sort of tunnel vision. This isn't something that more training would fix, and it's not something only a "stupid" pilot would do: this is a basic, unavoidable fact of human nature and the human brain. Screening out distractions and focusing solely on the task at hand is an excellent skill and one of the things that makes a good pilot a good pilot. Unfortunately, in this case, one of the "distractions" was the airport he actually meant to land at.
I've had flight students take me to the wrong county before, even when there is no other airport within 20 miles. That's because I sprung an "emergency" diversion on them right in the middle of their nicely-planned cross-country flight, they focused on an airport that they thought was the one I told them to divert to, and concentrated on flying to the airport they saw. It wouldn't be hard to go to the wrong one when there are 4 airports within 10 miles that all look a lot alike, as is the case with the 747 crew here.
Regarding (3), this doesn't happen every day or every month, but it does happen plenty of times that you don't hear about. Many general aviation pilots have picked the wrong airport, and small regional airliners have done the same on several occasions. The difference with them is that because they're much smaller aircraft, they simply blush, taxi back to the ample runway, and take off again without anyone ever being the wiser. (Except in the case of the regional airliners, because the onboard ACARS or similar system automatically reports landing and takeoff events to the airline office, so those pilots might get a bit of a raised eyebrow from the company without making headlines.)
Another friend pointed out this incident from NASA's Callback bulletin from October 2004 called "Lost, Alone, and in the Dark" that you probably didn't hear about because it didn't make the news:
In the end, the Air Force concluded its investigation of the C-17 incident by stating the cause as pilot fatigue. While it will be quite some time before the facts of this current incident come out, I suspect that in the end the final cause will boil down to a simple matter of human imperfection. It's easy to second-guess and Monday morning QB, but in reality good pilots are always trying to learn from the mistakes of others (you can't live long enough to make all of them yourself) without copping an attitude of, "That would never happen to me." That's a lesson that—like so may others—transfers well from the cockpit to everyday life.
The author is an airline pilot, flight instructor, and adjunct college professor teaching aviation ground schools. He holds an ATP certificate with a DHC-8 type rating, as well as CFI, CFII, MEI, AGI, and IGI certificates, and is a FAASafety Team representative and Master-level participant in the FAA's WINGS program. He is on Facebook as Larry the Flying Guy, has a Larry the Flying Guy YouTube channel, and is on Twitter as @Lairspeed.
It takes hours of work to bring each Keyboard & Rudder post to you. If you've found it useful, please consider making an easy one-time or recurring donation via PayPal in any amount you choose.
Follow on Twitter, too:
Follow @Lairspeed
A good friend sent me a story from CNN about a 747 that landed at the wrong airport last night and asked how it could happen. The short answer is that it's not as hard as it seems, especially under the circumstances.
For a while now, when teaching about situational awareness, I have used the example of this C-17 Globemaster crew that landed at Peter O. Knight airport in Tampa instead of MacDill Air Force Base where they had intended:
Thanks to the 747 crew, I have a second example of how easy it is to chase the wrong patch of concrete. Keep in mind that both of these examples happened to professional crews using modern equipment and avionics. (Update: USA today has a short rundown of how many times this has happened in just the last 10 years.)
When I started to read the story my friend sent me, I originally thought, "Oh, they must have landed at Mid-Continent instead thinking it was McConnell AFB. Both of them have long parallel runways heading in the same direction." I've been to Mid-Continent (center-left underneath the "WICHITA" below) and I remember when I was looking at the sectional chart during my flight planning I made a mental note as to how much McConnell looks like Mid-Continent and to double-check I was pointed at the right one once I got there.
 |
| Chart from vfrmap.com |
- crew going to a military, towered field lands at a non-towered field
- runways in similar configuration
- you actually heard about it happening
Tower controllers have lots of other things they're doing at the same time. The usual depiction of controllers as people staring at a radar screen unblinkingly with nothing else in front of them is only true of either center controllers or approach controllers. You've seen these time after time, including in the funny but underappreciated movie Pushing Tin with John Cusack, Billy Bob Thornton, and Angelina Jolie:
That stereotypical image isn't even remotely true of tower controllers because their job isn't to get aircraft from Point A to Point B. The aircraft has already made it almost to Point B and their job is to sequence them in line with other aircraft that may already be landing (or waiting to take off), and it's up to the pilot to actually land it. They might notice if the aircraft's blip (called a data block) drops off the radar early, but in this case they were in an area where radar coverage goes all the way to the ground (as the dotted magenta line surrounding AAO, the airport the 747 crew landed at, shows above). If the aircraft is in distress or the pilot tells the tower controller on initial contact that they're a student pilot, the controller will watch the display very closely, but for a routine flight flown by a highly experienced crew (no one just hops into one of the front seats of a 747 without thousands and thousands of hours) in the middle of the night with no other traffic around, its very easy to see why this wouldn't be noticed. After all, controllers can't fly the airplane, and they expect the people who are to do the job right.
Regarding (2), the only thing that surprised me about the C-17 in Tampa is that it hadn't happened even earlier or more often. Peter O. Knight looks much like a miniature version of MacDill, and it is directly in line for final with one of MacDill's runways. This is very similar to an environment the 747 crew was put in, as you can see by this sectional chart excerpt:
 |
| Chart from vfrmap.com |
In the Wichita chart excerpt above, I drew a cyan line connecting the two to emphasize how both runways go in the same direction and line up with the flight path of the 747 almost perfectly. At any time, but especially at night, these airports wouldn't look all that different from one another. Since I don't have the time to hop in the plane and fly the 700+ miles to take a good, real picture, here's a view of what the arrangement looks like at night in Microsoft Flight Simulator X from an altitude and distance they were likely to be at:
 |
| Click image to embiggen. |
There's the airport they landed at, from 4,000 feet and 10 miles out, which is my best educated guess at where they were. (Update 11/22: I dug up the flight's track log on FlightAware and that was one outstanding guess. That's pretty close to where they were at one point.) Did you notice the darker patch in the background? Yeah, they probably didn't either. That's because they were in the right vicinity, the heading was about right, the altitude was about right, and there was an airport right about where one should be. With that in mind, once the pilot flying saw the airport, his mind locked on to it and he concentrated only on flying safely down to it. Once the airport is in sight, even GPS or the FMS gets ignored, because the point of navigation systems is to get you to the point where you have the airport in sight.
The concentration required on approach forces the mind into a sort of tunnel vision. This isn't something that more training would fix, and it's not something only a "stupid" pilot would do: this is a basic, unavoidable fact of human nature and the human brain. Screening out distractions and focusing solely on the task at hand is an excellent skill and one of the things that makes a good pilot a good pilot. Unfortunately, in this case, one of the "distractions" was the airport he actually meant to land at.
I've had flight students take me to the wrong county before, even when there is no other airport within 20 miles. That's because I sprung an "emergency" diversion on them right in the middle of their nicely-planned cross-country flight, they focused on an airport that they thought was the one I told them to divert to, and concentrated on flying to the airport they saw. It wouldn't be hard to go to the wrong one when there are 4 airports within 10 miles that all look a lot alike, as is the case with the 747 crew here.
Regarding (3), this doesn't happen every day or every month, but it does happen plenty of times that you don't hear about. Many general aviation pilots have picked the wrong airport, and small regional airliners have done the same on several occasions. The difference with them is that because they're much smaller aircraft, they simply blush, taxi back to the ample runway, and take off again without anyone ever being the wiser. (Except in the case of the regional airliners, because the onboard ACARS or similar system automatically reports landing and takeoff events to the airline office, so those pilots might get a bit of a raised eyebrow from the company without making headlines.)
Another friend pointed out this incident from NASA's Callback bulletin from October 2004 called "Lost, Alone, and in the Dark" that you probably didn't hear about because it didn't make the news:
I preflighted the plane for a return flight to [another airport in Wisconsin]. The lighting on the instrument panel seemed faint, but the airport ramp was well lit. I adjusted the rheostat on the panel and departed. Once aloft, I could not easily read the instruments. Relying only on the compass, I became lost. I could not read the clock and lost track of time. After searching for an airport to put the plane down, I saw one with a runway open. I saw a plane approaching and, maintaining a safe distance, followed it in and landed. I took the first taxiway off the runway and shut down. I had not declared an emergency and was not in contact with the tower. It was O'Hare.
In the end, the Air Force concluded its investigation of the C-17 incident by stating the cause as pilot fatigue. While it will be quite some time before the facts of this current incident come out, I suspect that in the end the final cause will boil down to a simple matter of human imperfection. It's easy to second-guess and Monday morning QB, but in reality good pilots are always trying to learn from the mistakes of others (you can't live long enough to make all of them yourself) without copping an attitude of, "That would never happen to me." That's a lesson that—like so may others—transfers well from the cockpit to everyday life.
The author is an airline pilot, flight instructor, and adjunct college professor teaching aviation ground schools. He holds an ATP certificate with a DHC-8 type rating, as well as CFI, CFII, MEI, AGI, and IGI certificates, and is a FAASafety Team representative and Master-level participant in the FAA's WINGS program. He is on Facebook as Larry the Flying Guy, has a Larry the Flying Guy YouTube channel, and is on Twitter as @Lairspeed.
It takes hours of work to bring each Keyboard & Rudder post to you. If you've found it useful, please consider making an easy one-time or recurring donation via PayPal in any amount you choose.
Tuesday, November 19, 2013
Storm Kings from Mars
Review of Lee Sandlin's Storm Kings: The Untold History of America's First Tornado Chasers
METARs, TAFs, and other sources of aviation weather give the heights of cloud bases, but they do not give any information about what kind of clouds they are. The sole exception that you're likely to see is CB—cumulonimbus. After all, thunderstorms are important to know about because you don't want to fly into one. However, there is another exception, one that you're unlikely to see in your average everyday flying: FC—funnel cloud. Lee Sandlin's book is all over these and the people who study them, chase them, and obsess about them.
Ben Franklin is known for many things, and one of the images that probably comes to mind when you think of the name is the painting of him performing the famous key on a kite experiment. What you may not have known is that the author of Poor Richard's Almanack was also the author of studies on tornadoes and waterspouts, making him one of the founders of what would eventually become the modern science (and Weather Channel overdramatization) of storm chasing.
Sandlin moves deftly from Franklin to other major players in the birth of storm chasing (and, for that matter, weather prediction in general) such as James Espy, William Redfield, John Finley, Cleveland Abbe, E. J. Fawbush, Robert Miller, Ted Fujita, and others. He does not pretend that science is an impartial, unstoppable march where the success of ideas is solely due to the strength of the data that back them, but gets into the personalities, and the conflicts between those personalities, that gave shape to the early studies and debates.
Along the way, he takes us on visits to the trails of destruction left by tornadoes, which were then known as "wind roads" as they cut passages through the thickly-wooded lands of the early United States. Until the invention of the airplane, research on these was only able to be done slowly by painstakingly walking them and taking notes on the arrangement of debris. Ted Fujita (the "F" in "EF-5 tornado") was able to make much of the progress that he made by utilizing Cessna planes to fly him along these trails.
Sandlin gives us an account of the Peshtigo firestorm which spawned tornadoes of flame, incinerating villages and killing more people than any other fire in U.S. history. (The fire made the public relations blunder of happening on the same day as the Great Chicago Fire, which is why it's likely you've never heard of it despite its apocalyptic style.)
He drops in on Tinker Air Force Base and relates the story of the first successful prediction of a tornado, takes us to the Weather Bureau when it fit in a single unremarkable building, and recounts the damage done by several different tornadoes of historical proportions, and does almost all of it so well, with such good tie-in, that it's almost as much of a page-turner as a fiction novel would be.
In fact, the only real complaint is that once we go on this tour through a few centuries of storm-chasing history, he closes up shop and turns off the lights as soon as we get to the present day storm chasers. I can't fault him overly much for this for two reasons. First, there are several books already on the market about modern storm chasing, many of them written by the chasers themselves. Second, the book, by its very title, is intended to be a history of storm chasing, which means its subject matter excludes the present. True to form, almost the only mention made of modern storm chasing is in a rather short epilogue.
Summary: A fast read that is surprisingly entertaining for a history book. If you buy it through the link below, you help support Keyboard & Rudder at no cost to you:
What Sandlin left out was that tornadoes also happen on Mars. They even leave their own "wind roads", though theirs are through the dusty surface of the red planet instead of fallen trees. Check out the two images below for proof of extraterrestrial tornadoes:
METARs, TAFs, and other sources of aviation weather give the heights of cloud bases, but they do not give any information about what kind of clouds they are. The sole exception that you're likely to see is CB—cumulonimbus. After all, thunderstorms are important to know about because you don't want to fly into one. However, there is another exception, one that you're unlikely to see in your average everyday flying: FC—funnel cloud. Lee Sandlin's book is all over these and the people who study them, chase them, and obsess about them.
Ben Franklin is known for many things, and one of the images that probably comes to mind when you think of the name is the painting of him performing the famous key on a kite experiment. What you may not have known is that the author of Poor Richard's Almanack was also the author of studies on tornadoes and waterspouts, making him one of the founders of what would eventually become the modern science (and Weather Channel overdramatization) of storm chasing.
 |
| From one of Franklin's studies called "Water-spouts and Whirlwinds". Photo from NOAA's Photo Library at http://www.flickr.com/photos/noaaphotolib/ |
Along the way, he takes us on visits to the trails of destruction left by tornadoes, which were then known as "wind roads" as they cut passages through the thickly-wooded lands of the early United States. Until the invention of the airplane, research on these was only able to be done slowly by painstakingly walking them and taking notes on the arrangement of debris. Ted Fujita (the "F" in "EF-5 tornado") was able to make much of the progress that he made by utilizing Cessna planes to fly him along these trails.
Sandlin gives us an account of the Peshtigo firestorm which spawned tornadoes of flame, incinerating villages and killing more people than any other fire in U.S. history. (The fire made the public relations blunder of happening on the same day as the Great Chicago Fire, which is why it's likely you've never heard of it despite its apocalyptic style.)
He drops in on Tinker Air Force Base and relates the story of the first successful prediction of a tornado, takes us to the Weather Bureau when it fit in a single unremarkable building, and recounts the damage done by several different tornadoes of historical proportions, and does almost all of it so well, with such good tie-in, that it's almost as much of a page-turner as a fiction novel would be.
In fact, the only real complaint is that once we go on this tour through a few centuries of storm-chasing history, he closes up shop and turns off the lights as soon as we get to the present day storm chasers. I can't fault him overly much for this for two reasons. First, there are several books already on the market about modern storm chasing, many of them written by the chasers themselves. Second, the book, by its very title, is intended to be a history of storm chasing, which means its subject matter excludes the present. True to form, almost the only mention made of modern storm chasing is in a rather short epilogue.
Summary: A fast read that is surprisingly entertaining for a history book. If you buy it through the link below, you help support Keyboard & Rudder at no cost to you:
What Sandlin left out was that tornadoes also happen on Mars. They even leave their own "wind roads", though theirs are through the dusty surface of the red planet instead of fallen trees. Check out the two images below for proof of extraterrestrial tornadoes:
 | |||
| The arrow is pointing at a Martian dust devil. See http://hirise.lpl.arizona.edu/PSP_004285_1375 for more information. |
 | |
| The black squiggles are Martian "wind roads" created by dust devils as they wandered the surface, kicked up dust, and faded away. See http://hirise.lpl.arizona.edu/ESP_013538_1230 for more information. |
Friday, November 15, 2013
Man Dead After Falling Out of Airplane
A man in South Florida is feared to be dead after the door opened in the Piper Malibu he was flying in as a passenger on Thursday. Makes for great copy and an even better headline, but would it really happen? Not on your life (or his).
Despite what the movies would have you believe, even in the extremely rare cases when an entire section of fuselage rips off an airliner at over 30,000 feet, everyone inside doesn't get sucked out a big hole. In the even more rare cases that someone does get "sucked out", it is always someone like a flight attendant or other unlucky soul who happened to be standing up, unbuckled, right next to the opening.
This "sucking" only continues until the pressure inside the fuselage (which is much higher, since the people inside tend to consider enough oxygen to breathe as included in the price of the ticket) equalizes with the pressure outside. If the hole is large enough for a person to go through, this equalization will take place in a matter of seconds. After that, all that loud noise and wind will be from air outside the aircraft coming in just like the wind does when you roll down the windows in your car. (That's assuming your car has 10-foot windows and is going 500 MPH.) Take comfort in the knowledge that in almost all cases of pressurization problems, the loss of cabin pressure is slow and is caused by either a stuck valve in the system itself or a gap that opened up somewhere in between the pressurized and unpressurized parts of the aircraft that is small enough that even a @#$% snake on a @#$% plane couldn't squeeze through.
The reason I put "sucking" in scare quotes above is because the air inside the plane isn't being "sucked" out. In reality, what is happening is that the higher-pressure air inside is flowing violently outside to where the pressure is much lower. It's exactly the same principle as what happens when you blow up a balloon then instead of tying the end, you let the air come out, making a noise that sounds like a session of Congress. If you let the air come out long enough, eventually all of it will be gone and it will stop flowing.
Now that I've spent three paragraphs explaining what happens in airliners, I'll get to the Piper Malibu referred to in the news story by saying that it has almost nothing in common with an airliner. Even if the entire top of the aircraft fell off, its service ceiling is about 10,000 feet lower than an airliner's typical cruising altitude so the difference in pressure between inside and outside is much lower, the cabin is much, much smaller so there's less air to "suck", and it goes less than half as fast. In addition, it has a "Door Unlatched" annunciator light in the cockpit, so the pilot wouldn't be able to take off with the door ajar without knowing it. (I mention that because the pilot reported that he had an open door.)
Will an airplane fly with a door open? You bet it will. In fact, I've had doors unlatch on me in flight dozens of times; it's just one of those things that happens occasionally. Most of them are designed—just like the doors on your car—so that if they do accidentally come unlatched the air flowing past the fuselage will keep them pressed mostly closed. The plane itself doesn't care, and it will keep on flying happily along with almost no noticeable difference other than a higher-than-normal level of cockpit noise and a nice cooling breeze along the forehead (in Cirrus and Piper aircraft).
In fact, this is such a common occurrence in Piper Seminoles that when I took my CFII checkride, I semi-jokingly included in my pre-takeoff briefing to the examiner: "Once the door pops open on the takeoff roll, I will bring both throttles to idle, contact tower to let them know we are aborting the takeoff, exit at Taxiway E, secure the door once we are clear of the runway, and ask to taxi back for takeoff again." Can you guess what happened one minute later? (To be fair, this doesn't happen all the time. I only said it because I knew that a quirk of the particular aircraft I was in that day was that its door latch was like Jay Leno: old, worn out, and desperately in need of replacement.)
When a student is getting close to solo in a Cirrus, I will intentionally pop the door open in the traffic pattern to see how they react. If they continue around the pattern, land, and then address the door, I know they are doing just fine. The first priority of an aviator is always, always, always, no matter what happens, always fly the plane.
An open door isn't even an emergency, but most manufacturers have a procedure to handle it just in case. This usually boils down to a simple matter of slowing to about 80 knots, opening a window, and closing the door again. It is considered such a minor matter than some manufacturers actually put the "Door open in flight" checklist in the "Normal Procedures" section of the manual. Piper is not one of those, but they do have a checklist for it. The first few lines of it are simply:
Many aircraft will fly perfectly well even if a door is removed. Skydivers do that all the time, and I flew a Cessna 182 with the right door taken off when I dropped the famous Golden Knight turned motivational speaker Dana Bowman on one of his jumps in 2012. I could hardly tell a difference, other than with the weight of the right seat and door gone, the plane actually performed a bit better.
I'm not going to speculate on what actually happened in that Piper Malibu. That's for the investigators to figure out. All I'm here to do is to tell you what won't happen in an airplane: you won't fall out of one if you fly. So go out and enjoy it!
Despite what the movies would have you believe, even in the extremely rare cases when an entire section of fuselage rips off an airliner at over 30,000 feet, everyone inside doesn't get sucked out a big hole. In the even more rare cases that someone does get "sucked out", it is always someone like a flight attendant or other unlucky soul who happened to be standing up, unbuckled, right next to the opening.
This "sucking" only continues until the pressure inside the fuselage (which is much higher, since the people inside tend to consider enough oxygen to breathe as included in the price of the ticket) equalizes with the pressure outside. If the hole is large enough for a person to go through, this equalization will take place in a matter of seconds. After that, all that loud noise and wind will be from air outside the aircraft coming in just like the wind does when you roll down the windows in your car. (That's assuming your car has 10-foot windows and is going 500 MPH.) Take comfort in the knowledge that in almost all cases of pressurization problems, the loss of cabin pressure is slow and is caused by either a stuck valve in the system itself or a gap that opened up somewhere in between the pressurized and unpressurized parts of the aircraft that is small enough that even a @#$% snake on a @#$% plane couldn't squeeze through.
The reason I put "sucking" in scare quotes above is because the air inside the plane isn't being "sucked" out. In reality, what is happening is that the higher-pressure air inside is flowing violently outside to where the pressure is much lower. It's exactly the same principle as what happens when you blow up a balloon then instead of tying the end, you let the air come out, making a noise that sounds like a session of Congress. If you let the air come out long enough, eventually all of it will be gone and it will stop flowing.
Now that I've spent three paragraphs explaining what happens in airliners, I'll get to the Piper Malibu referred to in the news story by saying that it has almost nothing in common with an airliner. Even if the entire top of the aircraft fell off, its service ceiling is about 10,000 feet lower than an airliner's typical cruising altitude so the difference in pressure between inside and outside is much lower, the cabin is much, much smaller so there's less air to "suck", and it goes less than half as fast. In addition, it has a "Door Unlatched" annunciator light in the cockpit, so the pilot wouldn't be able to take off with the door ajar without knowing it. (I mention that because the pilot reported that he had an open door.)
Will an airplane fly with a door open? You bet it will. In fact, I've had doors unlatch on me in flight dozens of times; it's just one of those things that happens occasionally. Most of them are designed—just like the doors on your car—so that if they do accidentally come unlatched the air flowing past the fuselage will keep them pressed mostly closed. The plane itself doesn't care, and it will keep on flying happily along with almost no noticeable difference other than a higher-than-normal level of cockpit noise and a nice cooling breeze along the forehead (in Cirrus and Piper aircraft).
In fact, this is such a common occurrence in Piper Seminoles that when I took my CFII checkride, I semi-jokingly included in my pre-takeoff briefing to the examiner: "Once the door pops open on the takeoff roll, I will bring both throttles to idle, contact tower to let them know we are aborting the takeoff, exit at Taxiway E, secure the door once we are clear of the runway, and ask to taxi back for takeoff again." Can you guess what happened one minute later? (To be fair, this doesn't happen all the time. I only said it because I knew that a quirk of the particular aircraft I was in that day was that its door latch was like Jay Leno: old, worn out, and desperately in need of replacement.)
When a student is getting close to solo in a Cirrus, I will intentionally pop the door open in the traffic pattern to see how they react. If they continue around the pattern, land, and then address the door, I know they are doing just fine. The first priority of an aviator is always, always, always, no matter what happens, always fly the plane.
An open door isn't even an emergency, but most manufacturers have a procedure to handle it just in case. This usually boils down to a simple matter of slowing to about 80 knots, opening a window, and closing the door again. It is considered such a minor matter than some manufacturers actually put the "Door open in flight" checklist in the "Normal Procedures" section of the manual. Piper is not one of those, but they do have a checklist for it. The first few lines of it are simply:
If both upper and side latches are open, the door will trail slightly open and airspeeds will be reduced slightly.
To close the door in flight.
Slow airplane to 82 KIAS.
Cabin vents ... close
Storm window ... open
Many aircraft will fly perfectly well even if a door is removed. Skydivers do that all the time, and I flew a Cessna 182 with the right door taken off when I dropped the famous Golden Knight turned motivational speaker Dana Bowman on one of his jumps in 2012. I could hardly tell a difference, other than with the weight of the right seat and door gone, the plane actually performed a bit better.
I'm not going to speculate on what actually happened in that Piper Malibu. That's for the investigators to figure out. All I'm here to do is to tell you what won't happen in an airplane: you won't fall out of one if you fly. So go out and enjoy it!
Thursday, November 14, 2013
House, you are cleared for takeoff
Several years ago, someone came up with the neat idea of taking a retired Boeing 747 out of the boneyard and making it into a house. A few closed highways later (747 wings don't exactly fit on the back of an F-150 pickup truck), and the house is now complete.
The results are more imaginative than just plopping an aircraft down on a lot, taking out the seats, putting in new carpet, and calling it done. Instead, this is a house that is made out of 747 parts, not just a 747 that was made into a house.
Architecturally, it is interesting in its own right, but what I find most interesting about it is actually being able to see the shape of the airfoil at the wing root. Since wings taper at the end, getting thinner and changing into a more flattened shape, and then hiding the rest of the aeronautical design in winglets at the tip, it is hard to see that the same Bernoulli-inspired design that you see in the generic textbook airfoil is also at the heart of the 747's wing.
Sometimes it's easy to forget that the same principles that apply to a little Cessna 172 also apply to a huge Boeing 747, but the pictures of this house make it blatantly obvious that they do. Physics is physics, and you can see that for yourself here with one of the coolest examples around at Houzz Tour: A Salvaged Airplane Becomes a Soaring Hillside Home.
The results are more imaginative than just plopping an aircraft down on a lot, taking out the seats, putting in new carpet, and calling it done. Instead, this is a house that is made out of 747 parts, not just a 747 that was made into a house.
Architecturally, it is interesting in its own right, but what I find most interesting about it is actually being able to see the shape of the airfoil at the wing root. Since wings taper at the end, getting thinner and changing into a more flattened shape, and then hiding the rest of the aeronautical design in winglets at the tip, it is hard to see that the same Bernoulli-inspired design that you see in the generic textbook airfoil is also at the heart of the 747's wing.
Sometimes it's easy to forget that the same principles that apply to a little Cessna 172 also apply to a huge Boeing 747, but the pictures of this house make it blatantly obvious that they do. Physics is physics, and you can see that for yourself here with one of the coolest examples around at Houzz Tour: A Salvaged Airplane Becomes a Soaring Hillside Home.
Thursday, November 7, 2013
An Incredible Forecast from an Incredible Storm
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It was one year ago that Hurricane Sandy impacted the East Coast of the United States. Its incredible size allowed it to cause more damage than the average hurricane. Unlike many storms, whose effects are felt in a relatively more compact area, Hurricane Sandy unleashed her winds and precipitation over multiple states at the same time.
In fact, while New Jersey and New York were bracing for their direct hit, Hurricane Sandy was kicking up strong winds and rain all the way to Cleveland, Ohio. These winds and clouds caused some relatively minor (compared to NY/NJ) damage around the area and gave me a stretch of several days off from flying due to Terminal Area Forecasts (TAFs) such as this:
I've had a few posts recently where I go into how to use a TAF and how not to. But what if you're still not sure what all that "secret code" means? Well, why don't we review how to read a TAF by decoding one you won't forget?
This screenshot is the combined METAR and TAF output from aviationweather.gov's lookup service. Where I fly, I usually pull up the forecasts for the two closest airports that have them to get a bigger, more accurate idea of what the weather is going to do, which is why this contains both KCLE (Cleveland-Hopkins) and KMFD (Mansfield-Lahm).
First the METAR:
KCLE 300251Z 34036G48KT 6SM +RA BR OVC014 06/04 A2951
I'll truncate the stuff beginning with RMK because while it's information that's "nice to know", it's not "need to know". I want to focus on the meat of the METAR without bogging you down in details.
KCLE: (Cleveland-Hopkins International Airport)
300251Z: Look at it as 30/0251Z - The 30th day of the month (October) at 2:51 a.m. Greenwich Mean Time (Zulu)
34036G48KT: Look at it as 340/36/G48 with a KT to remind you that it's knots. In other words, winds are from 340 (northwest; this is a true direction not magnetic, since this is a text report) at 36 knots with gusts (G) to 48 knots. That's 41-55 MPH. The light sport aircraft I was teaching in at the time would take off without moving in a wind like this.
6SM: The SM conveniently reminds you that this is something in statute miles. About the only thing ever given in aviation that isn't in nautical miles is visibility. Therefore, visibility 6 miles.
+RA: heavy (+) RAin
BR: mist. The reason it's not "MI" is because everybody hates Michigan so much that they'd rather use an abbreviation for the French word "brume", which means "mist".
OVC014: skies are OVerCast beginning at 1400 feet above ground level.
06/04: temperature 6° Celsius (43° Fahrenheit), dew point 4° C (39° F). The two numbers being so close usually means there will be some low clouds. That's kind of anti-climactic, since we just saw that the sky was totally covered in clouds (overcast) at only 1400 AGL.
A2951: Altimeter setting (i.e., the barometric pressure) 29.51" Hg. That's really low, especially considering Hurricane Sandy's center is hundreds of miles away.
Combining all these little facts into something useful, we can see that on the night of October 29-30, 2012, in Cleveland the weather was very chilly under solid clouds, and it was so windy that cats and small dogs were being blown away, then falling back to the ground as heavy rain. It's got to get better sometime, right?
That's where the TAF comes in. And then says, "Umm, no, actually."
KCLE 300253Z 3003/3106 35030G50KT P6SM -RA OVC015
TEMPO 3003/3005 3SM RA SCT008 OVC015
FM300500 34030G50KT 3SM RA BR OVC006
FM301400 34025G40KT 4SM -RA BR OVC006
FM302300 30018G30KT 5SM -RA BR OVC006
TAFs and METARs use similar terminology and format, so if you understand one, you understand about 80% of the other.
KCLE: (Cleveland-Hopkins International Airport)
300253Z: The date and time of a METAR are when the observation was taken. The date and time of a TAF are in the same format (in this case, the 30th day of the month at 2:53 a.m. Greenwich Mean Time) but are when the forecast was released.
3003/3106: Valid from the 30th at 3:00 a.m. Z to the 31st at 6:00 a.m. Z
35030G50KT: When this forecast was issued, the winds were from 350 (north) at 30 knots gusting to 50 knots.
P6SM: visibility is Plus (i.e., greater than) 6 statute miles
-RA: light (-) RAin
OVC015: skies are OVerCast beginning at 1500 feet above the ground
TEMPOrarily, from the 30th at 3:00 a.m. Z for the next two hours, it's going to get even worse. The visibility is going to decrease to only 3 statute miles, some scattered clouds are going to drop down around 800 feet above the ground and then it's going to be solid clouds starting at 1500 feet above the ground.
FRom the 30th at 5:00 a.m. Z, the winds are going to keep on blowing, the rain is going to become moderate instead of light, and it's going to stay cloudy, with the clouds coming down to 600 feet above the ground.
FRom the 30th at 2:00 p.m. Z, the wind is going to stay strong although slightly weaker, the visibility is still going to be cruddy but slightly better, and the rain is going to slightly but not completely let up.
FRom the 30th at 11:00 p.m. Z, ditto the preceding paragraph.
Condensing that forecast into something useful like we did with the METAR, we can see that the whole day is going to blow. Literally. To help you see just how much it blows, here are the surface analysis and weather depiction charts for that time:
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It was one year ago that Hurricane Sandy impacted the East Coast of the United States. Its incredible size allowed it to cause more damage than the average hurricane. Unlike many storms, whose effects are felt in a relatively more compact area, Hurricane Sandy unleashed her winds and precipitation over multiple states at the same time.
In fact, while New Jersey and New York were bracing for their direct hit, Hurricane Sandy was kicking up strong winds and rain all the way to Cleveland, Ohio. These winds and clouds caused some relatively minor (compared to NY/NJ) damage around the area and gave me a stretch of several days off from flying due to Terminal Area Forecasts (TAFs) such as this:
 |
| It's cold, rainy, and the winds are gusting to almost 50 knots. Let's not fly today. |
This screenshot is the combined METAR and TAF output from aviationweather.gov's lookup service. Where I fly, I usually pull up the forecasts for the two closest airports that have them to get a bigger, more accurate idea of what the weather is going to do, which is why this contains both KCLE (Cleveland-Hopkins) and KMFD (Mansfield-Lahm).
First the METAR:
KCLE 300251Z 34036G48KT 6SM +RA BR OVC014 06/04 A2951
I'll truncate the stuff beginning with RMK because while it's information that's "nice to know", it's not "need to know". I want to focus on the meat of the METAR without bogging you down in details.
KCLE: (Cleveland-Hopkins International Airport)
300251Z: Look at it as 30/0251Z - The 30th day of the month (October) at 2:51 a.m. Greenwich Mean Time (Zulu)
34036G48KT: Look at it as 340/36/G48 with a KT to remind you that it's knots. In other words, winds are from 340 (northwest; this is a true direction not magnetic, since this is a text report) at 36 knots with gusts (G) to 48 knots. That's 41-55 MPH. The light sport aircraft I was teaching in at the time would take off without moving in a wind like this.
6SM: The SM conveniently reminds you that this is something in statute miles. About the only thing ever given in aviation that isn't in nautical miles is visibility. Therefore, visibility 6 miles.
+RA: heavy (+) RAin
BR: mist. The reason it's not "MI" is because everybody hates Michigan so much that they'd rather use an abbreviation for the French word "brume", which means "mist".
OVC014: skies are OVerCast beginning at 1400 feet above ground level.
06/04: temperature 6° Celsius (43° Fahrenheit), dew point 4° C (39° F). The two numbers being so close usually means there will be some low clouds. That's kind of anti-climactic, since we just saw that the sky was totally covered in clouds (overcast) at only 1400 AGL.
A2951: Altimeter setting (i.e., the barometric pressure) 29.51" Hg. That's really low, especially considering Hurricane Sandy's center is hundreds of miles away.
Combining all these little facts into something useful, we can see that on the night of October 29-30, 2012, in Cleveland the weather was very chilly under solid clouds, and it was so windy that cats and small dogs were being blown away, then falling back to the ground as heavy rain. It's got to get better sometime, right?
That's where the TAF comes in. And then says, "Umm, no, actually."
KCLE 300253Z 3003/3106 35030G50KT P6SM -RA OVC015
TEMPO 3003/3005 3SM RA SCT008 OVC015
FM300500 34030G50KT 3SM RA BR OVC006
FM301400 34025G40KT 4SM -RA BR OVC006
FM302300 30018G30KT 5SM -RA BR OVC006
TAFs and METARs use similar terminology and format, so if you understand one, you understand about 80% of the other.
KCLE: (Cleveland-Hopkins International Airport)
300253Z: The date and time of a METAR are when the observation was taken. The date and time of a TAF are in the same format (in this case, the 30th day of the month at 2:53 a.m. Greenwich Mean Time) but are when the forecast was released.
3003/3106: Valid from the 30th at 3:00 a.m. Z to the 31st at 6:00 a.m. Z
35030G50KT: When this forecast was issued, the winds were from 350 (north) at 30 knots gusting to 50 knots.
P6SM: visibility is Plus (i.e., greater than) 6 statute miles
-RA: light (-) RAin
OVC015: skies are OVerCast beginning at 1500 feet above the ground
TEMPOrarily, from the 30th at 3:00 a.m. Z for the next two hours, it's going to get even worse. The visibility is going to decrease to only 3 statute miles, some scattered clouds are going to drop down around 800 feet above the ground and then it's going to be solid clouds starting at 1500 feet above the ground.
FRom the 30th at 5:00 a.m. Z, the winds are going to keep on blowing, the rain is going to become moderate instead of light, and it's going to stay cloudy, with the clouds coming down to 600 feet above the ground.
FRom the 30th at 2:00 p.m. Z, the wind is going to stay strong although slightly weaker, the visibility is still going to be cruddy but slightly better, and the rain is going to slightly but not completely let up.
FRom the 30th at 11:00 p.m. Z, ditto the preceding paragraph.
Condensing that forecast into something useful like we did with the METAR, we can see that the whole day is going to blow. Literally. To help you see just how much it blows, here are the surface analysis and weather depiction charts for that time:
 |
| Surface analysis for October 30, 2012 at 0300z. Hurricane Sandy stands out as the big L with the closely-spaced isobars surrounding it. |
 |
| Weather depiction chart for October 30, 2012 at 0400z. |
Tuesday, November 5, 2013
Flight Training in 76 Seconds
Learning to fly is one of the best things you will ever do in life. The feeling of awe and accomplishment once you fly an airplane all by yourself for the first time creates one of those memories that practically every pilot remembers forever. If you don't believe me, find the oldest pilot you can and ask them if they remember their first solo.
However, it's not always a linear progression. Along the way, everyone has setbacks, bad flying days, or maneuvers they just can't seem to perfect. At some point, everyone wonders if they'll ever solo or pass the dreaded checkride. Once you do, all that anxiety and frustration that seemed almost insurmountable is forgotten.
Again, if you don't believe me, ask this mouse if all the trouble was worth it:
(I came across this video originally at kottke.org/13/11/meet-the-most-determined-mouse-in-the-world.)
That little mouse had one bad landing after another, don't you think? In fact, 55 seconds through, it thought hard about giving up and walked away, just as most people would. However, just when it looked like it was going to fail, it took a step back, regrouped and gathered its focus, and tried again. Defeat is temporary; failure is permanent.
Keep this mouse in mind if you're worrying about a maneuver, studying for a written exam, getting ready for a checkride, working on an instrument rating and trying to figure out holding pattern entries or decipher approach charts, or whatever hurdle you happen to be struggling with at the time, whether it be in flying or life in general.
Have any experiences you thought you'd never overcome during training? Share it in a comment below and help someone who may be going through the same thing thinking they were the only one. Or share an experience that made you feel like all that work had finally paid off.
However, it's not always a linear progression. Along the way, everyone has setbacks, bad flying days, or maneuvers they just can't seem to perfect. At some point, everyone wonders if they'll ever solo or pass the dreaded checkride. Once you do, all that anxiety and frustration that seemed almost insurmountable is forgotten.
Again, if you don't believe me, ask this mouse if all the trouble was worth it:
That little mouse had one bad landing after another, don't you think? In fact, 55 seconds through, it thought hard about giving up and walked away, just as most people would. However, just when it looked like it was going to fail, it took a step back, regrouped and gathered its focus, and tried again. Defeat is temporary; failure is permanent.
Keep this mouse in mind if you're worrying about a maneuver, studying for a written exam, getting ready for a checkride, working on an instrument rating and trying to figure out holding pattern entries or decipher approach charts, or whatever hurdle you happen to be struggling with at the time, whether it be in flying or life in general.
Have any experiences you thought you'd never overcome during training? Share it in a comment below and help someone who may be going through the same thing thinking they were the only one. Or share an experience that made you feel like all that work had finally paid off.
Saturday, November 2, 2013
Hidden Weather Secrets, Literally
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In the modern world, we take the miracle of weather forecasting for granted. While the TV weather forecaster is the popular butt of jokes about the quality of their predictions, nowadays they're right way more often than they're wrong.
They've even gotten better at being wrong. Today, instead of the weather turning out to be gorgeous on a day that was supposed to be rainy or vice versa, forecasts in recent years tend to be wrong about the amount of rain or clouds or what time it will start. This is an underappreciated improvement over being flat-out wrong.
There is a team of thousands of people using cutting-edge computers, sensors, and research (mixed with a dose of "poke your head out the window and look up") that make analyses such as this one routine:
Thanks to the pile of technology and knowledge churned together at government weather offices every hour of every day, pilots, sailors, farmers, picnic goers, and dog walkers can hop on the internet, go to their favorite weather source, and know within minutes whether it's a good day to fly, if the crops will need watered today, or if Fluffy would fly away if you took her to the park for her walk.
Nothing in life comes free, and although we may not have paid a fee for the website we went to in order to get this information, millions of dollars of tax money goes to places like the NWS, NOAA, etc. to produce these forecasts. Considering that these forecasts save lives by keeping planes and ships out of weather they can't handle and save millions of dollars in crops and other products by warning of conditions that will affect them, we actually get a pretty good return on that money.
In fact, as an interesting historical note, the very first successful, specific forecast of a tornado occurred in 1948 at Tinker Air Force Base in Oklahoma. Because the base had a few hours of warning that there would probably be tornadoes that afternoon, they took steps to move aircraft into hangars and other shelters. The predicted tornado did happen, and because of the precautions taken, approximately $4 million ($40 million in 2013 dollars) of taxpayer-paid-for planes and equipment was saved.
Unfortunately, in October 2013, the gamesmanship of the U.S. government sequester turned into a EF-5 tornado of political windbaggery, leading to a government shutdown. Politicians and bureaucrats recognized the importance of maintaining forecasters on the job looking out for weather that might affect us. Throughout the shutdown, they were deemed essential personnel and went to work every day.
However, the dysfunction led to many departments without the funding to actually pay the people they deemed "essential". This led to the forecast above, which, while technically accurate, also contained a hidden message. Read the first letter of each line to find it. To help you out, I've highlighted the message in red below:
The author is an airline pilot, flight instructor, and adjunct college professor teaching aviation ground schools. He holds an ATP certificate with a DHC-8 type rating, as well as CFI, CFII, MEI, AGI, and IGI certificates, and is a FAASafety Team representative and Master-level participant in the FAA's WINGS program. He is on Facebook as Larry the Flying Guy, has a Larry the Flying Guy YouTube channel, and is on Twitter as @Lairspeed.
It takes hours of work to bring each Keyboard & Rudder post to you. If you've found it useful, please consider making an easy one-time or recurring donation via PayPal in any amount you choose.
Follow on Twitter, too:
Follow @Lairspeed
In the modern world, we take the miracle of weather forecasting for granted. While the TV weather forecaster is the popular butt of jokes about the quality of their predictions, nowadays they're right way more often than they're wrong.
They've even gotten better at being wrong. Today, instead of the weather turning out to be gorgeous on a day that was supposed to be rainy or vice versa, forecasts in recent years tend to be wrong about the amount of rain or clouds or what time it will start. This is an underappreciated improvement over being flat-out wrong.
There is a team of thousands of people using cutting-edge computers, sensors, and research (mixed with a dose of "poke your head out the window and look up") that make analyses such as this one routine:
 |
| Just another day at the weather office. |
Thanks to the pile of technology and knowledge churned together at government weather offices every hour of every day, pilots, sailors, farmers, picnic goers, and dog walkers can hop on the internet, go to their favorite weather source, and know within minutes whether it's a good day to fly, if the crops will need watered today, or if Fluffy would fly away if you took her to the park for her walk.
Nothing in life comes free, and although we may not have paid a fee for the website we went to in order to get this information, millions of dollars of tax money goes to places like the NWS, NOAA, etc. to produce these forecasts. Considering that these forecasts save lives by keeping planes and ships out of weather they can't handle and save millions of dollars in crops and other products by warning of conditions that will affect them, we actually get a pretty good return on that money.
In fact, as an interesting historical note, the very first successful, specific forecast of a tornado occurred in 1948 at Tinker Air Force Base in Oklahoma. Because the base had a few hours of warning that there would probably be tornadoes that afternoon, they took steps to move aircraft into hangars and other shelters. The predicted tornado did happen, and because of the precautions taken, approximately $4 million ($40 million in 2013 dollars) of taxpayer-paid-for planes and equipment was saved.
Unfortunately, in October 2013, the gamesmanship of the U.S. government sequester turned into a EF-5 tornado of political windbaggery, leading to a government shutdown. Politicians and bureaucrats recognized the importance of maintaining forecasters on the job looking out for weather that might affect us. Throughout the shutdown, they were deemed essential personnel and went to work every day.
However, the dysfunction led to many departments without the funding to actually pay the people they deemed "essential". This led to the forecast above, which, while technically accurate, also contained a hidden message. Read the first letter of each line to find it. To help you out, I've highlighted the message in red below:
 |
| Click image to embiggen. |
The author is an airline pilot, flight instructor, and adjunct college professor teaching aviation ground schools. He holds an ATP certificate with a DHC-8 type rating, as well as CFI, CFII, MEI, AGI, and IGI certificates, and is a FAASafety Team representative and Master-level participant in the FAA's WINGS program. He is on Facebook as Larry the Flying Guy, has a Larry the Flying Guy YouTube channel, and is on Twitter as @Lairspeed.
It takes hours of work to bring each Keyboard & Rudder post to you. If you've found it useful, please consider making an easy one-time or recurring donation via PayPal in any amount you choose.
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