# The Great Ongoing Aviation Thread (general and other) (Part 1) **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [October 23, 2011, 2:17am UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499 "2011-10-23T02:17:01Z")\ **Posts on this page:** 20\ **Page:** 391
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [May 4, 2025, 4:54pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7803 "2025-05-04T16:54:51Z")
Rob Holland video - [Why I Fly the MXS](https://www.youtube.com/watch?v=LjMN7iCxVY0) I’m trying to figure out the weight plug in the elevator. Even though the elevator is massive the weight doesn’t look like something that is catastrophic. There’s a good closeup of the weight in the NTSB report posted above by **smithsb** ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [May 4, 2025, 7:54pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7804 "2025-05-04T19:54:30Z")
When the badly-secured weight shifts in flight and jams the motion of the elevator, it’s the elevator locked at an undesired displacement that is catastrophic. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [May 4, 2025, 9:29pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7805 "2025-05-04T21:29:10Z")
Seems like an awful design to me: [![Imgur](https://i.imgur.com/ZbsbAZf.png "imgur.com") ](https://imgur.com/ZbsbAZf) Clearly, either the screw plug coming undone or the cylindrical weight sliding partly out could jam the elevator into a very unfortunate position. It should have some other positive locking mechanism, whether safety wire or otherwise. ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [May 6, 2025, 3:34am UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7806 "2025-05-06T03:34:01Z")
If this happened at 2,000 ft AGL could an aerobatic pilot rotate the plane 90 deg and use the rudder as an elevator to regain altitude control? At 50 it’s just chaos trying to regain control but at higher altitudes there is time to figure out what is going on. I remember a DC-8 crash where the jack screw on the elevator went full up. The crew made continuous turns to control altitude. They almost made it but misjudged the turn to final and came up short into a car lot causing a massive fire. Not exactly the same scenario but they used 3 axis control of the plane to overcome a stuck elevator. ---
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [May 6, 2025, 8:10am UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7807 "2025-05-06T08:10:32Z")
Maybe. In hindsight You can sometimes come up with a specific control input that might have worked. That said, the elevator can easily be jammed in a way that just doesn’t work for any attitude. Full up being the obvious example. I’ve no doubt mentioned this before on this long thread, but Neil Williams was an aerobatic pilot who had a wing fold up in flight and recovered by flying an inverted circuit to a (crash) landing. [Aerobatic Accident - Emergency Landing — FLYING THINGS](https://www.flyingthings.org/flying-articles/the-day-the-wing-fell-off). _. . to 1000 ft where experiments were carried out to determine whether the aircraft could be rolled out to normal flight and, if so, to establish the optimum direction. A roll out to the left was attempted, but the wing started to fold, so inverted flight was quickly re-established.’_ In reality most of us can only hope to hang on and not swear too much on our way down. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [May 6, 2025, 10:34am UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7808 "2025-05-06T10:34:10Z")
Agree w @Richard_Pearse. Rolling 90 degrees solves the problem that the jammed elevator is driving the nose upwards relative to Earth. It does bupkiss to solve the problem that the jammed elevator is driving the nose upwards relative to the plane itself. Depending on how extreme the jam was, the elevator may be forcing so much G on the airplane that something is gonna break. Or so much G that more power is required to maintain airspeed than is available. There are certainly stories of miraculous saves. And also stories of miraculous saves until they could not transition from “mostly-controlled flight” near the ground to “safely stopped in one piece on the ground.” On every flight it’s worth remembering that you’re not done dying until the chocks are in and you’re back in the building. ---
**Author:** ![WildaBeast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wildabeast/32/6_2.png) [@WildaBeast](https://boards.straightdope.com/u/WildaBeast)\ **Post date:** [May 6, 2025, 4:19pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7809 "2025-05-06T16:19:55Z")
> [@Magiver](#): > > I remember a DC-8 crash where the jack screw on the elevator went full up. The crew made continuous turns to control altitude. They almost made it but misjudged the turn to final and came up short into a car lot causing a massive fire. Is this the crash you’re thinking of? It was actually local to me, although it happened a few years before I moved to the area. But it’s something long time residents remember and will tell you about. > **[Emery Worldwide Airlines Flight 17](https://en.wikipedia.org/wiki/Emery_Worldwide_Airlines_Flight_17)** > > Emery Worldwide Airlines Flight 17 was a regularly scheduled United States domestic cargo flight, flying from Reno, Nevada to Dayton, Ohio with an intermediate stopover at Rancho Cordova, California. On February 16, 2000, the DC-8-71F operating the flight crashed onto an automobile salvage yard shortly after taking off from Sacramento Mather Airport, resulting in the deaths of all three crew members on board. The crew reported control problems during takeoff and attempted unsuccessfully to retu... ---
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [May 7, 2025, 8:08am UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7810 "2025-05-07T08:08:55Z")
What is it with F/A-18 fighter jets falling off the USS Harry S. Truman? **[A second one just fell off](https://www.cbc.ca/news/world/second-fighter-jet-falls-off-carrier-1.7528391)** the same aircraft carrier within about a week. Maybe they shouldn’t park them so close to the edge? 😉 OK, to be fair, this was a failed landing. But losing two $60 million jets within a week? Someone is going to have some uncomfortable questions to answer. ---
**Author:** ![Spiderman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/spiderman/32/230_2.png) [@Spiderman](https://boards.straightdope.com/u/Spiderman)\ **Post date:** [May 7, 2025, 1:51pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7811 "2025-05-07T13:51:32Z")
> [@wolfpup](#): > > What is it with F/A-18 fighter jets falling off the USS Harry S. Truman? **[A second one just fell off](https://www.cbc.ca/news/world/second-fighter-jet-falls-off-carrier-1.7528391)** the same aircraft carrier within about a week. Coulda been worse, I mean the [front didn’t fall off](https://www.youtube.com/watch?v=3m5qxZm_JqM) Maybe we should rename it the USS [Britney Spears](https://www.youtube.com/watch?v=CduA0TULnow&t=89s) ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [May 7, 2025, 9:38pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7812 "2025-05-07T21:38:49Z")
> [@WildaBeast](#): > > Is this the crash you’re thinking of? It was actually local to me, although it happened a few years before I moved to the area. But it’s something long time residents remember and will tell you about. Yes. If I remember correctly it was a full up elevator situation and they almost pulled it off. ---
**Author:** ![PastTense](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pasttense/32/14550_2.png) [@PastTense](https://boards.straightdope.com/u/PastTense)\ **Post date:** [May 7, 2025, 10:02pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7813 "2025-05-07T22:02:03Z")
Preliminary report is out on the New York City helicopter crash a month ago which killed 6: [https://t.co/jjGb6aSrP9](https://t.co/jjGb6aSrP9) ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [May 7, 2025, 10:19pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7814 "2025-05-07T22:19:47Z")
> [@Richard\_Pearse](#): > > Maybe. In hindsight You can sometimes come up with a specific control input that might have worked. I don’t think there was a hindsight in this situation. At 50 ft there isn’t any time to figure out what is going on. I was asking about a jammed elevator at a much higher altitude where there is the possibility of time to work things out. Doesn’t rolling it 90 deg swap the elevator for the rudder in flight control? ---
**Author:** ![Spiderman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/spiderman/32/230_2.png) [@Spiderman](https://boards.straightdope.com/u/Spiderman)\ **Post date:** [May 8, 2025, 12:58pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7815 "2025-05-08T12:58:18Z")
This struck me as odd > [@NTSB prelim report](#): > > At that time, the helicopter airframe accrued 12,975 total hours of > operation, and the engine had accrued a total of 23,305 hours of operation I would have guessed that, if anything, they’d replace the engine on an airframe; unless it’s a typo, they put a used engine into that helo. Is that common? ---
**Author:** ![Robot\_Arm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/robot_arm/32/18280_2.png) [@Robot\_Arm](https://boards.straightdope.com/u/Robot_Arm)\ **Post date:** [May 8, 2025, 2:46pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7816 "2025-05-08T14:46:26Z")
> [@Magiver](#): > > Doesn’t rolling it 90 deg swap the elevator for the rudder in flight control? In a sense, but having the rudder stuck fully to one side has been know to bring planes down, too. ---
**Author:** ![WildaBeast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wildabeast/32/6_2.png) [@WildaBeast](https://boards.straightdope.com/u/WildaBeast)\ **Post date:** [May 8, 2025, 3:54pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7817 "2025-05-08T15:54:12Z")
> [@Spiderman](#): > > I would have guessed that, if anything, they’d replace the engine on an airframe; unless it’s a typo, they put a used engine into that helo. Is that common? IIRC it’s not uncommon for engines to get swapped around between airframes. Rather than take the entire aircraft out of service because the engine needs maintenance, it’s faster and cheaper to remove the engine and send it out for maintenance, and swap in another good engine. That allows them to get the aircraft back in service relitively quickly. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [May 9, 2025, 1:27am UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7818 "2025-05-09T01:27:32Z")
> [@Magiver](#): > > Doesn’t rolling it 90 deg swap the elevator for the rudder in flight control? Sort of. I guess you skipped my last post. It changes the relationship between the elevator and rudder in earth-centric coordinates. But not in airplane-centric coordinates. After rolling 90 degrees, the airplane may be just as uncontrollable, but now it’s trying to corkscrew laterally, not nose up into a loop. ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [May 9, 2025, 3:39am UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7819 "2025-05-09T03:39:00Z")
I read your earlier post, I just didn’t understand it. I can throw full rudder against ailerons with full control of a small plane. I would think it would work similarly if the plane is turned 90 degrees. A stuck elevator becomes a stuck rudder. What I don’t know is the ratio of lift between a rudder and an elevator. If an elevator has twice the force against a fuselage than a rudder then that changes the dynamics of the question. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [May 9, 2025, 11:48am UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7820 "2025-05-09T11:48:38Z")
I think you’re hung up on what “up” means. In an airplane there are always two "up"s. The one from the center of the earth towards the sky and the one from the bottom of the wheels up towards the top of the vertical fin. In straight and level flight the two ups are aligned. They are _not_ the same, but they are _aligned_. In inverted flight the airplane-centric up and the earth-centric up are directly opposed. In a conventional 30 degree banked turn, the ups are misaligned by 30 degrees. With the result that some of the airplane’s lift forces pull it around the turn. And, that means those lift forces aren’t available to counteract gravity, so to maintain altitude while turning somehow you need to add lift in the earth-centric up direction. Which we do with some back pressure and added power. More total lift in the airplane-up direction is created, and it is divided between pulling the airplane around the turn and holding the airplane up at a constant altitude against ever present gravity. So far so familiar, if maybe explained in terms more appropriate to an aerobatic pilot than a cross-country cruiser pilot. Now switching to the stuck elevator scenario … If you had an elevator hard over, that will force the airplane’s nose upwards _in airplane-centric_ coordinates. And that resulting turning in the airplane’s vertical plane of motion will put positive G-force on the overall airplane & wings, and negative G forces on the tail. Rolling 90 degrees (just for concreteness let’s say to the left, so left wing down, right wing up) does nothing to change those things. The airplane is still being uncontrollably G’ed. And will keep turning in the airplane-centric vertical plane. What _does_ change, as you say, is that now the elevator / G induced turn will be in the horizontal plane when viewed in Earth-centric coordinates. So you’ll be making an extremely tight left turn from the earth POV, perhaps with enough G on the wings to break them right off the airplane. Meanwhile, while you’re in 90 degree knife-edge flight, there’s no force holding you up against gravity. So you’ll be plummeting earthward & viewed in 3D your tight left turn is actually a tight spiral downwards. With a powerful enough rudder you can yaw the nose in the airplane right = earth up direction. And get some lift in the earth up direction from the left side of the fuselage being exposed to the relative wind directing it downwards. Fuselages are very inefficient wings, and most airplanes cannot maintain altitude and airspeed in knife-edge flight. The ones that can are high-powered aerobatic planes with huge engines who can more or less hang on the prop, held up as much by the partly downward-directed prop thrust as by lift from the fuselage. And meanwhile there’s enough prop thrust available along the line of flight to keep the airspeed up despite the drag from the yawed fuselage. Bottom line: Starting from straight and level flight, a stuck or hard over up elevator will cause the nose to be uncontrollably raised skyward in an attempted loop which quickly will run you out of airspeed and lead to a stall or spin. Rolling 90 degrees stops the “skyward” part. But that’s all. The stuck elevator is still uncontrollably pulling the airplane nose _up_ in airplane-centric coordinates. Which is now parallel to the horizon, but still uncontrolled / uncontrollable. ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [May 10, 2025, 7:45pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7821 "2025-05-10T19:45:01Z")
> [@LSLGuy](#): > > Rolling 90 degrees stops the “skyward” part. But that’s all. The stuck elevator is still uncontrollably pulling the airplane nose _up_ in airplane-centric coordinates. Which is now parallel to the horizon, but still uncontrolled / uncontrollable. You can still control direction of flight with S turns and altitude with power. But you have to have enough altitude to start the process. 50 feet off the ground is not that altitude. ---
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [May 11, 2025, 8:30am UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/7822 "2025-05-11T08:30:04Z")
It appears that one of the requirements for airline pilots should be **[the ability to distinguish left from right](https://www.msn.com/en-ca/news/world/pilot-sets-airplane-brakes-on-fire-after-confusing-left-right-hands-investigation-finds/ar-AA1Extq0?ocid=msedgntp&cvid=2597308b0e64470ab287c5d45c8d63ab&ei=17)**. [Previous page](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499.md?page=390) [Next page](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499.md?page=392)