He used to race experimental cars. He was in a horrific crash on one of those salt flats and his personality was permanently changed. He went from being pleasant to the person I knew him as-- cold, strange and reclusive.
Turns out he was coming in to the office just long enough to use Excel to run a calculation. He was designing a helicopter where the jet engines were on the tip of the rotors and you stood in a can above the whirling blades. We called it GarbageCopter.
Anyways, he eventually gave up and bought a gyrocopter. He flies that thing all day, every day. Just circling in the pattern at our airport at 1,000 feet and 20 knots.
He is very old and blind on one side. I have no idea how he got his health check. I am pretty sure he will be a statistic someday, but at least he's doing something he likes.
Sort of like Wittgenstein himself.
Notoriously, Stanislaw Ulam and Steve Wozniak had major personality changes after head trauma.
In January 1946, he suffered an acute attack of encephalitis, which put his life in danger, but which was alleviated by emergency brain surgery.
Another friend, Gian-Carlo Rota, asserted in a 1987 article that the attack changed Ulam's personality: afterwards, he turned from rigorous pure mathematics to more speculative conjectures concerning the application of mathematics to physics and biology; Rota also cites Ulam's former collaborator Paul Stein as noting that Ulam was sloppier in his clothing afterwards, and John Oxtoby as noting that Ulam before the encephalitis could work for hours on end doing calculations, while when Rota worked with him, was reluctant to solve even a quadratic equation.
And even more famously, Henry VIII, who fell off a horse.
From personal experience, they care a great deal about your eyesight.
To start, you'd want to look through the AME Guide  and the rules in 14 CFR 67 Part D .
(I also wasn't even sure about ultralights not requiring licenses. Had to look it up.)
If it was not traumatic brain injurie, like others mentioned, I can maybe give an other point of view.
I guess it is the struggle of acceptance. Everyone knows accidents happen, but before you were in a bad one and have high self esteem, you likely believe, this won't happen to you. That would be unfair.
"Those things cannot happen to me" - well, yes, they absolutely can happen to you. Why not to you? Why not to me?
I had that with a actually not so serious sport accident, which still meant I could not do sport for years - which was a very serious crisis for me. WHY ME?
Well, why not me. In hindsight I would rather think I was very lucky, to not have that accident, while being somewhere far off.
Today I can even do (moderate) extreme sports again, ... but much more aware of what I am doing and how easy it is, to loose it all.
So I can allmost say, today I am thankful for that accident, but I can also see, how such a accident can bring you to a very dark place of where you cannot get out.
Your former boss seems to need his flying to get out of it at least for some time. I guess there are worse ways to cope with it.
Edit: I mean push on the stick. Sorry, had a brainfart. Good thing I'm not a pilot.
> Fatal Sequence
> As the rotor is unloaded, both control thrust and the drag of the rotor disc fall off rapidly. With a high engine thrustline (relative to the vertical c.g. and center of drag) and/or with a momentary gust that can increase fuselage drag, the gyro can pitch forward and tumble. Such tumbling, also known as bunting over, can occur almost instantly. There is no possible recovery, and bunting over is invariably fatal.
I don't understand how a gyroplane flies, or why pulling back on the stick causes immediate problems. But ... should autogyros have controls where you describe the motion you want, and let a computer figure out the actuation?
I think there's an analogy to software here, where generally we're less error-prone and more productive if we can specify what we want by expressing higher-level, declarative relationships, rather than demanding that humans always think in terms of the low-level operations that will need to occur.
The thing I found funny when reading into that is that, for all that effort for roll and pitch, the rudder is just hydraulic. I suppose there's just not that many ways you can fancy up yaw control.
> However, Sullenberger said that these computer-imposed limits also prevented him from achieving the optimum landing flare for the ditching, which would have softened the impact.
That said the cases for this are probably very, very rare.
If you have muscle memory trained in one system, you tend to revert to that behavior when under stress.
What's your backup plan when your flight control computer crashes? Or if you have an electrical failure?
(There's an argument to have computers provide additional assistance on top of the manual systems, but we usually stop short of fundamentally remapping flight controls. And even then, we have to be careful otherwise we end up with situations like MCAS.)
The general approach for critical hardware like flight controllers is triple redundant systems with two-out-of-three voting, driving redundant actuators.
MCAS is a prime example of this NOT being followed, because it relied on a single sensor input to generate a significant control output.
In almost all single-rotor helicopters, pushing the nose over — fixed wing style — runs a high risk of causing the tailboom to rise and collide with the main rotor. The rare rigid rotor ships (BO-105s, mostly) are less likely to have this happen.
I kind of assumed that "the one thing you instinctively do to escape a stall" is to push forward on the stick. Some answeres here seem to confirm that: https://aviation.stackexchange.com/questions/49865/why-does-...
From the other discussion I linked, it sounds like the issue is that the rotor normally creates forward drag, and earlier designs have the engine/thrust propeller mounted pretty high. Pushing the stick forward causes the rotor to have less forward drag than it normally does, so the engine thrust effectively causes the whole craft to pitch forward. Which is sort of what you'd expect to happen when you push forward on the stick, but I guess it happens in a way that's hard/impossible to correct from.
I'm not sure why (given sufficient altitude) you can't cut the engine and recover using autorotation the way a normal helicopter can, but I imagine it's pretty hard to do this in a normal helicopter too if you're falling upside-down.
edit: this parent comments makes more sense if instead the author meant push on the stick, as another pointed out.
You mean push on stick? (that's what is done to avoid stall in normal aircrafts)
If there's an expert, I'd love to hear if what I just wrote is correct.
A good picture of this setup:
Edit Addendum: Typically loss of control in a nose down situation for autogyros is because they don't have ailerons to control roll. They rely on the cyclic of the rotor disk.
And they could be cheaper to build and easier to operate?
There is one particular brand of autogyro that can take off vertically by pre-spinning the rotor and then applying collective at the same time as disconnecting power from it. They tend to leap off the tarmac. But that is not the norm. Standard autogyros require a takeoff roll just as a fixing aircraft plane does. People often look at the rotor and think that it is like a helicopter but in fact it is more like a fixed wing aircraft in the sense that air must be passing over the wings / rotor in order to produce lift.
That being said, an autonomous autogyro does sound very interesting. One could pre-spin the rotor with a typical brushless motor and then leave it unpowered during flight. It does require collective control to be able to do that but even hobby helicopters have collective and cyclic control, so adding just collective control seems very approachable.
Source: I'm an expert flyer with dozens of seconds flying. I once bought my kid a tiny 2" drone and eventually took over as pilot. Now I didn't take it from him, he just stopped playing with it (What's wrong with kids these days? I would've loved it as a kid) but those little things are so fun to fly.
Quadcopters don't really scale past a fairly small point before the efficiency nosedives though.
Also they have a single large unducted rotor that's easy to destroy or hurt someone with, and you can't have automatic collision avoidance, because you can't easily stop an autogyro in mid-air.
Then graduated early and left the building.
Take controlled flight into terrain, a common enough problem that aviation safety writing just calls it CFIT. This is when an aircraft collides with terrain, but there was no loss of control. CFIT is a relatively common occurrence, but why does someone fly a completely controllable aircraft into the ground? Almost always due to perceptual confusion, disorientation either to attitude or location. Unintended entry into instrument conditions (e.g. into a cloud or fog bank) is one cause, but disorientation can occur for a number of other reasons as well, including in good weather conditions.