Amazing footage. I’m sure the video distorts perspective but it looks like they were very lucky the plane didn’t hit a skydiver after spinning.
I know very little about aviation but this seems like a pretty foolish and avoidable incident. I would have thought there would be a procedure for how many people can leave or hang from the back of the plane as it would very obviously affect how it flies. I can’t imagine that sort of manoeuvre is good for the airframe?
A 9 person exit is not at all unusual. We used to do a 10-way angle track at sunset every day. Larger formations are both possible and routine. As long as the pilot is aware of and can anticipate the weight shifting there's generally no issue at all.
You are right that there is a clear limit to the number of people allowed on the outside step set by the DZ. In the original video you can count the heads on climb-out and these jumpers are exceeding every guideline that I've been subject to. My formations adhere to five outside and one crouched, max - but do note that several bodies may follow the exit with as little delay as possible. We try to exit as a unit. I'm only a coach with ~500 jumps, by no means an authority.
This model plane in particular is less forgiving and the airspeed is high on jump run. As skydivers we are cautioned about the exits and take extra care to maintain a forward CoG. I have experience with aerodynamic modelling and private pilot training but won't speculate other than to say that structural integrity is not an issue. It's more like capsizing a boat than overloading a trailer hitch.
At my local drop zone one of our pilots posted this video as a reminder of why we let the pilot know when we have large groups leaving the plane. Large groups outside like this can starve the elevator of airflow, and the sudden change in center of gravity is also a factor.
This seems like a weakness of a king air as a jump plane. The pilot has to throttle down the left engine so jumpers aren’t thrown into the tail on exit by the prop wash. I’m happy with our single-engine super caravan with its wide door so not so many people have to be outside to do big groups like this.
> ...it looks like they were very lucky the plane didn’t hit a skydiver after spinning.
I always find it interesting how we underestimate the expanse of 3D space depending on the view: jumpers are exactly between the airplane and camera, which is not surprising since the cameraperson and jumpers came from the direction of the airplane, with the camera going out first.
From another angle (eg satellite view from above or a sideways view), I am sure the distance between jumpers and the plane would be more obvious. Still risky (you wouldn't plan on passing that close), but not as much as it seems.
Absolutely, you are right about the distance. But the thing is, I think risk is not measured in meters.
The question more is what made sure that the airplane didn't re-contact the skydivers. When an airplane after the drop flies on straight and steady you know that they wont hit the skydivers because the skydivers have no propulsion and relatively lot of drag. The skydivers will lose horizontal speed quickly and gain vertical speed downwards even quicker. This basically guarantees that the separation between the squishy humans and the airplane will be maintained.
With the spinning airplane staying close to the divers who knows. Maybe the pilot is an ACE and they kept a mental model of the parachutist's position relative to theirs at all times. Maybe what appears to us as uncontrolled tumbling is anything but. Or maybe it was just up to "luck".
My mental model is that the biggest risk is the turning turboprop.
The rest of the dynamics fall out from that: during the dive, the engine on the divers' side is already off, and once the stall happens, the pilot cuts off both engines (to avoid a spinning engine hitting anyone), dives to gain speed.
Being inside the plane as a jumper during the recovery was probably the least pleasant -- normally one doesn't have a seatbelt in that scenario. I think at 0:54 one more person falls out the open jump door?
While I agree a part of it was "luck", I think you've already highlighted some of the "variables" about why they weren't "very lucky" (as GP proclaimed) — difference of drag (in all dimensions), difference of speed and any active efforts by all sides.
I like to turn question like this on its head: how would you make an airplane hit those skydivers on the way down? If the answer is: "very fricking hard", I think the "luck" plays a small role.
Basically, if they were hit, they would have instead been "very unlucky". :)
Aside from the fact that the skydivers weren't really that close to the plane during the recovery, it was pretty much just luck. In a situation like that training takes over, and the only thing you're really looking out for is the ground to keep your bearings straight.
"One of the jumpers [exited later]. She was tossed around inside the aircraft and ended up on the floor next to the door. During the final motions of the aircraft she bounced off the door frame and out the door."
If I was in the airplane getting tossed about like that, I would be scrambling like mad to get out!
Just to embellish and clarify: During my first jump training, one of the things the instructor drilled into us was "You have a parachute. If something goes wrong and you need to save your life, use it!".
Mr Browne / Blancolerio has some fantastic flight information and covers most USA based crashes and subsequent FAA investigations in great detail. Highly recommended if you're even vaguely interested in flying.
If you read the comments, two commenters (one claiming experience piloting quite a few different plane types as a skydiver pilot, as well as plenty of hours on King Air planes) suggest that the pilot here was doing it wrong, and that there's no need (and it's dangerous) to throttle back the engine on the side that the skydivers jump out of. Anyone here experienced enough to comment on this claim?
You don't "need to" but reducing the prop wash is a nicety.
It's the kind of thing the pilot does in commercial operations (to improve the customer experience) when there's textbook perfect VFR conditions and 10k of margin below you if you run out of power/lift and have to dive out of a stall. It suffices to say marines jumping out of the back of C17s and C130s are not getting that kind of polite treatment. Even if you've got a bunch of well practiced skydivers, having them all get out of the plane quickly and close together is going to make for a much better experience for them.
Everyone is gonna pearl clutch about it being "dangerous" but prop washing the crap out of your skydivers also carries some danger. As the video indicates a stall at 10kft isn't really a big deal for a halfway competent pilot. I wouldn't call it a daily occurrence but elevator pilots (skydive pilots) recover from a stall far more than most because they're constantly climbing as fast as possible (because that's the most economic way to run a skydive operation). Considering the kind of pilots who wind up doing skydive operations I think a lot of them would have been tempted to just take their hands off the controls and see if the plane recovers itself (it should) and then intervene if it doesn't.
There is no real "answer" here because the activities involved have some baseline danger to them and at best you can just shift it around between parties.
Imagine the fallout if someone bumps the horizontal stabilizer on the way out the door and does even the slightest damage to it or gets a minor fracture or something. It's a big f-ing mess. A stall and a bunch of hand wringing is clearly the better outcome for all parties.
> As the video indicates a stall at 10kft isn't really a big deal for a halfway competent pilot
I don't know about that. I count at least two secondary stalls while the pilot was trying to recover. Or maybe you are saying the pilot is not halfway competent?
Not a pilot, but my interpretation is that the pilot probably tried to slow down to make the jump easier. That got him closer to the stall speed. Having one engine with less thrust is something twin engine pilots train a lot for (engine out scenario) but also something that puts you closer to stall speeds. The rudder is the primary way to control airplane direction when you are close to stall speeds because you lose aileron controls around that time (they don't do much when you stall). It's also what you use during engine out and what can trigger a spin during a stall. Now having the center of gravity change would be dangerous under those circumstances.
Stall recovery is also something pilots train for as that is highly dangerous during takeoffs and landings. A landing is basically a controlled stall. Spin recovery is less commonly trained for because it basically means you messed up the stall recovery, which should not happen. Sounds like the pilot did the correct thing (eliminate async trust and nose down).
So, not a good incident but it happened at an altitude where there was plenty of time to recover.
Also not a pilot but my understanding is that spins in multiengine aircraft are generally considered extremely dangerous, to the extent that they aren't even spun in testing/certification. From here^[1]:
> No multiengine airplane is approved for spins, and their spin recovery characteristics are generally very poor. It is therefore necessary to practice spin avoidance and maintain a high awareness of situations that can result in an inadvertent spin.
In something like a Caravan this might not be such a big deal (though I don't know about their stall-spin characteristics) but deliberately courting stall-spin in a big twin like a King Air by using asymmetrical thrust so close to stall seems extraordinarily dangerous bordering on reckless, even if you aren't counting the presence of skydivers near the out-of-control aircraft. The fact that it's established practice doesn't mean it's safe; it can just as easily be a "normalization of deviance" sort of thing.
As other commenters have mentioned, I think bringing both engines back to low power or idle, and accepting a moderate sink rate during the jump, would be much safer. That way, even if you do stall, you at least aren't doing it in an asymmetrical thrust condition.
If there is a sizable sink rate, or higher speeds, the odds of a jumper hitting the elevator or other parts of the plane are higher. We used to have to watch out even on little Cessna 182s - in the right conditions someone could easily hit it and rip it off, then everyone is in a world of hurt.
Regarding higher airspeed, I'm not suggesting that they go any faster—only that they burn altitude to maintain airspeed instead of flying level on asymmetrical thrust.
Regarding sink rate, in the absence of a definitive source I don't really buy that a moderate sink rate (again, with the same low airspeed) is going to significantly increase the risk of somebody hitting the tailplane. In the absurd extreme of a vertical dive, I guess a skydiver would probably be outpaced by the aircraft due to their different terminal velocities, but a shallow dive is a very different picture.
It’s not uncommon to be a foot from the elevator on some models of jump planes - when flying level, and without ‘floating’ out the door like some folks are prone to do. As with many things, ‘it depends’. Most jumpers aren’t going to be happy burning the altitude they just bought with their jump ticket so the pilot can be a little lazier though.
Most jumpers probably have no idea how dangerous it is to spin a multiengine aircraft, and anybody who would classify as "lazy" a pilot's avoidance of an asymmetrical thrust condition a hair above stall with a large, draggy mass hanging off the opposite side of the aircraft is, frankly, not really qualified to opine on the subject.
Spinning a King Air is, from an aviation safety point of view, unacceptable. Accidents happen, but the point is that great pains must be taken to prevent them from happening again; and if the skydiving community wants to convince the aviation community at large that this procedure is perfectly safe, they really need to show that what happened here was a freak accident rather than a totally predictable one. That will be a tall order, because it was a totally predictable accident.
Safety needs to take precedence over convenience. If the King Air can't run skydiving operations safely and conveniently, maybe it should not be used for skydiving operations.
At some point during landing the wing has to stall. Certainly a 3 point landing in a taildragger is taught as an uncontrolled crash from 2 inches above the ground. The reality is more complex as different parts of the wing will be experiencing different conditions and different wing features (flaps, steps, bugs, dings etc).
Controlled descent and touch down does not require stall. Not sure where you’re getting that but in my type (sr22), touch down is at speeds considerably above stall speed in landing configuration.
Ref Approach (100% flap) -> 85-90kt
Stall (100% flap) - 59kt
And documented stall speeds are when the wingtips and ailerons start losing effectiveness - the wing still generates plenty of lift.
This might be a different schools of thought then? The way my flight instructor explained to me (Cessna 150) that you can land very smoothly without stalling, but if your airplane has the energy you are still flying. Just you are doing it 0 inches above the runway. If any outside disturbances increase your energy or redirect you (such as a gust of wind, or a bump on the grass field) you become airborne again and the chances of messing things up increases from there. (bunny hopping etc...) So he expected this stall from 4 inches from me, and told me off if he couldn't hear the stall warning whistle come on at the last moment just before touchdown.
That being said I also heard that this is absolutely not how one should land an airliner. This type of landing would cause a tail strike there. So who knows. Maybe my trainer was old school. Maybe what is correct on a Cessna 150 on a grass field is not correct on your type or airfield.
This may be a matter of loose terminology - in the flare (and when slowing down in level flight generally), once you have reached the angle of attack giving the maximum coefficient of lift, you will descend (and therefore, in the flare, touch down.) Though there will be some flow separation at this point (and before) it is still a couple of degrees from a full-blown stall.
Stall is about airflow separation, not lift force. You can most definitely not have enough lift for flight, but not at enough angle of attack to be in a stall.
A stall is fundamentally a loss of lift from the airflow leaving a lift producing configuration. Some people might use it as a ‘stall from 2”’ to describe landing, but it’s fundamentally undesirable in controlled flight (which includes getting wheels on the ground). You don’t actually stall at 2”, and if you were that is a very bad idea as a gust of wind can mean you’ll randomly stall at 20ft next time and crash.
A stall is when the wing stops producing lift due to reduced air speed. Plane wings do not stall during landing. They produce lift all through the landing process. The plane uses flaps [0] to reduce the stall speed of the wings so they continue producing lift as the plane slows down. In the final stage of landing, the plane uses ground effect to produce lift at even slower speeds.
Yes, and accept that the aircraft will lose some height.
Asymmetric thrust, flaps down, large group disrupting airflow over horizontal stabilizer and creating a substantial CofG shift to aft, what could go wrong ...
I recently learned that this is an issue that bomber pilots / airplanes must deal with, when they deploy their payloads.
Here is a video of a test pilot giving a talk at MIT on the F-22 and its advanced flying capabilities which --as he puts it-- makes flying an F-22 actually easier than a Cessna.
"The thing they don't want you to know..." (/clickbait_headline)
Nary a King Air has counter-rotating props. As such, they all have a critical engine. Beechcraft as a company is sort of like the black-box storage providers of the 2000s pre-cloud IT world. They're not doing anything better than anyone else, with the exception of marketing...
The terms you wanna google here if you're curious and not familiar are "P-factor" and "adverse yaw."
There are lots of better airplanes to toss parachute jumpers out of than a King Air for this reason. For that matter, there are a lot better airplanes for the owner of this airplane in question to take his family to Aspen or Grand Cayman in, for the exact same reason.
If the aforementioned early 2000s IT storage salesman responds to a question of how you recover from disk failure with "don't have a disk failure," you would probably walk away not not buy his black box, right? Yet people buy King Airs because they bought a Baron before it, and bought the Baron because it was just a Bonanza with two props.
"What's going on with all these King Air crashes?" [1]
“The aircraft behaved very well, and the recovery was surprisingly easy,” Xei wrote.
Sounds like the pilot is talking about the simplest thing in the world. Video makes the pilot seem incredibly calm in the face of the plane moving in a crazy way.
Edit: what would make the plane move that way?--it seems to recover after initial spin only to drop nose down, then start strafing (correct term?) left and right like it's in a half pipe before starting to spin again. It looks almost totally of control, to me it looks like it hit a wall of air. I have no idea. I'm amazed the pilot was so cool. Very impressive
Get the airframe under controlled flight, then avoid obstacles and fly towards safe landing, then tell control & other aviators about the situation so they can help (or at least not worsen it).
When I learned to fly gliders we practised spins and spin recovery. First time I did it, I botched the recovery and was mildly terrified. Went up a week later with a extremely experienced instructor and spent a whole hour thermalling up to altitude, stalling, then using the rudder to kick it into a spin, cancel the rotation, kick it into an opposite spin and back, stalled the whole time. Lose 3000 feet, recover, thermal back up, do it all over again. Very interesting to feel the complete ineffectiveness of the ailerons vs very effective rudder. By the end of it, I was pretty confident I would recognize the symptoms early and had the muscle memory to react quickly and correctly if I ever needed to. Best flying lesson I ever had.
Of course all that is with no engines. Assymetric thrust in a twin is more complicated, and I expect you've got less margin before you damage the airframe.
I haven’t done the training but friends have. My understanding is spin recovery is pretty standard. You enter the spin by a pretty intentional stall procedure.
From what I’ve heard it’s actually pretty frightening the first few times, but that’s the point - do it enough to recognize what’s happening and make the response automatic.
When I learned in the US, stall and spin avoidance and recovery was taught, but only stalls were actually practiced (because apparently too many accidents happened practicing spins). Not sure how the situation is in South Africa.
Spins recover practice is required for CFI (certified flight instructor), but not for PPL (private pilot license).
Many commercial pilots (like skydiving pilots) have CFI (because while training, you need to meet a certain number of flight hours, and you might as well spend them on CFI).
My information is very old, but my understanding is that in Canada, spin recovery is also required for private pilot's license. My father definitely had to put the plane into a spin and recover it in order to get his (now long expired) license.
Might depend on where you get your training from but I know for my private pilot's license I was instructed and practiced how to purposely get into spins and recover from them. It's a requirement in Canada: https://tc.canada.ca/en/aviation/publications/stall-spin-awa...
Spin avoidance, sure, but most places these days don't have actual spins on the syllabus as more were being lost in training practice than subsequent general flying.
Perhaps because the training wasn't being well done. It's a pity, because to most pilots a spin will be very disorienting unless you are used to it.
There is a website that has final audio recordings from actual incidents
Pilots remain calm
Only like confused new pilots in groups panic. For the rest, you can basically retrain your ear to tell when a pilot is more-so disillusioned by their self-preservation efforts.
When you’re spinning like this you don’t have control, it just happens to you. The dangerous part of being in a spin like this isn’t being able to regain control, if you push up the throttle it just happens. The dangerous part is damaging the airframe in the process (too much force “too many g’s) will rip the wings off or do permanent damage that requires the plane to be scrapped.
I know very little about aviation but this seems like a pretty foolish and avoidable incident. I would have thought there would be a procedure for how many people can leave or hang from the back of the plane as it would very obviously affect how it flies. I can’t imagine that sort of manoeuvre is good for the airframe?