+1 for the briefing of Pax (I’d for one would never have thought of this) but if it happens, the Pax’s instinctive reaction might just be to press harder.
There might be parallels with the elderly driver / automatic car phenomenon. When terror strikes with no braking action, the driver simply pushes harder on the accelerator which they have inadvertently chosen instead of the brake, and it takes longer to work out what’s wrong than the time to impact. Even some motorway ‘runaways’ might be explained this way. The authorities seem slow to recognise the problem and there’s no re-training when a person switches from manual to auto, sometimes late in life.
I’ve no idea if many or all 150/152 have this control cable vulnerability, but is there a case for some sort of shielding in the footwell? Or would that just make things worse, by occasionally jamming the controls with the added component?
Cobalt wrote:
I find it surprising that it was impossible to counter this with the control wheel – it has a much longer lever arm
A leg has a much longer lever arm (not to mention mass and strength!) than an actual arm, so if you measure the effective lever action for a leg on the lower part of the elevator control tube and measure the effective lever action for the pilot’s arm on the yoke, it will probably turn out that the leg has the advantage. Add to that a passenger who stiffens with fear when the plane suddenly dives, and you’ve got a recipe for a really bad day.
I recall my first aeros leasson which so happened to be in a side by side aircraft.
“In the event you freeze on the controls, or pass out, my left arm will move with some force onto and across the centre of your chest in order to free you from the controls. You may suffer some bruising and post impact trauma ;-)”
Fortunately I never felt the force of the left arm, but it wasnt an idle threat, as it had been used in earnest before! I am glad to say I have also not been the provider of the arm in reversed roles.
It was a serious point however and someone passing out slumped on the yoke in an aerobatic aircraft is not a happy combination, nor likely to reveal itself as the true cause of an accident if the pilot is unable to manage the situation. At such times there is a lot to be said for a stick.
Aveling wrote:
I’ve no idea if many or all 150/152 have this control cable vulnerability, but is there a case for some sort of shielding in the footwell?
There is cover over the assembly shown in the original post. I don’t know whether you can sneak your toe around the cover somehow but (assuming his design is common with the 120/140) seventy one years of experience hasn’t shown a lot of evidence of a problem.
From what I recall reading, a lot of the planes fly without that cover, because it is made from vacuum formed plastic and after many years it cracks and falls apart.
I’ve never seen a 150/152 without the cover, and Page 4 of the report shows the cover in place but regardless exposed control linkages is hardly a unique thing. Take a look at this Auster cockpit as an example. I view this as a typical Euro ‘shock horror’ melodrama. How long until an AD that’s adopted by some countries, delayed by others and debated for 10 years before being ignored although its still technically on the books for some kinds of operations, maybe 
As do most we have a rule no metal pens or other objects in the cockpit – ever. In an aerobatic aircraft they are potentially just as dangerous as trim removed.
Both our 172s — including the latest 172S model — have the same arrangement. This is what it looks like in our 172R:
I tried pushing the cable and pulling the yoke at the same time. I’m convinced that if you push on the cable with a straight leg it will be very difficult, if not impossible, for the pilot to counter.
