The damage just 1 washer can do

[Ultralights]

http://lessonslearned.faa.gov/ChinaAirlines120/ChinaAirlines120_Downstop_pop_up.htm

 

loss of a 737 from just 1 washer.

 

 

[facthunter]

Doesn't take much sometimes. Like the small elbow in the lube circuit on the A-380 engine, machined offcentre. Nev

 

 

[cscotthendry]

When I was in the USAF, we used to have FOD lectures during Commander's Call. During one of those, they told us how an F4 Phantom was lost in Viet Nam because of a washer. They called the story the $10 million washer.

 

What supposedly happened was a maintenance tech dropped a washer in the cockpit and didn't retrieve it. Later while the aircraft was flying inverted low over the ground, the washer jammed in the stick mechanism preventing the pilot from moving the stick. Both the aircraft and pilot were lost.

 

Washers are very dangerous things loose in aircraft.

 

 

[Gnarly Gnu]

If that info on the 737 is correct this comes across as a poor design.

 

 

[Guest Maj Millard]

I recall we lost a Chipmunk west of Sydney doing aeros because a coin got stuck in the base of the control stick. Found there later beat to hell...he had been trying to dislodge it............keep those stick boots in good shape !...I recall one Mirage being lost at Williamtown because a single screw came adrift in the intake. Found it imbedded in a turbine blade...And while I'm on the subject, one literally shot itself down at the range one day. Fired the guns in a dive without decelerating , caught up to the rounds and ingested one, causing loss of the aircraft...........Maj......

 

 

[David Isaac]

The Chipmunk incident was a 50 cent coin found in the wreckage with the imprint of the control column leverage forces. It prevented the stick from full forward position required in the Chipmunk for spin recovery. Both Pilots died in that incident.

 

 

[Guest Maj Millard]

David, Last time I checked 'west of Sydney' was in Australia I think...............

 

 

[David Isaac]

David, Last time I checked 'west of Sydney' was in Australia I think...............

ha ha is that better LOL

 

 

[Guest Maj Millard]

And speaking of loosing things......on a recent 100 hourly on a Savvannah I found several badly rusted split pins on aileron and flap hinge bolts, and critical control linkages. This was not simple surface corrosion, but the pin itself was rapidly returning to iron oxide, and had lost its safetying ability. This is one reason I like to use only stainless split pins these days. Make sure you check the integrity of your split pins !...Even the best quality steel coated split pin would be lucky to last a fortnight on a working seaplane (as an example )..........Maj.......

 

 

[facthunter]

David , the instructor in that DHC-1 was a good friend of mine. The jury is still a bit out on Chipmunk spin recovery. FULL forward stick may cause the plane to go into an inverted spin. IF you want to go down that path be prepared to "centralise the controls as soon as the recovery "Bites", But I personally would think you couldn't catch it quick enough to be sure (to be sure .. as the Irishman said). Nev

 

 

[deadstick]

One of my old flight instructors told me a story from his days flying Mig21's, he was flying at altitude and started feeling resistance against the elevator controls to the point it would jam then go past sort of like a notch, he RTB'd after a controllability check and U/S'd the aircraft for maintenance. The fault could not be replicated and the aircraft was released to service, a few days later another pilot reported the same issue, further inspections revealed nothing it wasn't until months later the aircraft in question was operating in a sub zero environment and experienced the same fault, upon RTB the maintenance staff again started investigations, this time due to the fact that it was still frozen they found that an ear plug had been freezing and jamming the controls inside the yoke assy, previously it had been freezing at altitude but had thawed during decent. Simple things!!!

 

 

[facthunter]

The screw jack that actuated the pitch trim on the B 727 would freeze sometimes if things were really cold up high. I've seen minus 58 C. This requires flight at warmer temps till it thaws out. Later a better grease was used and this wasn't a problem. There is a massive trim change from cruise to flap extend speeds and you couldn't hold the elevator against the pressure for any reasonable time, so it was a serious matter. Nev

 

 

[cooperplace]

literally shot itself down at the range one day. Fired the guns in a dive without decelerating , caught up to the rounds and ingested one, causing loss of the aircraft...........Maj......

which aircraft was that in?

 

 

[Guest Maj Millard]

which aircraft was that in?

Mirage A3-70 ....3 Sqn. at Williamtown (salt ash range) on 30/10/68, actually it was a ricochet off the ground that got it, as it passed over the target after firing, a common problem..........Maj.....

 

 

[Dafydd Llewellyn]

David , the instructor in that DHC-1 was a good friend of mine. The jury is still a bit out on Chipmunk spin recovery. FULL forward stick may cause the plane to go into an inverted spin. IF you want to go down that path be prepared to "centralise the controls as soon as the recovery "Bites", But I personally would think you couldn't catch it quick enough to be sure (to be sure .. as the Irishman said). Nev

My (limited) experience of spinning Chipmunks is that they will go flat - it's rather peaceful and quiet, actually, watching the horizon go past; the rate is fairly slow - and will recover, but it takes FULL forward stick and about three full turns, during which the rate of rotation increases, so the ground is a rotating blur - until it finally snaps out abruptly. Yes you needed to get the forward stick off pretty quickly, but I never had any trouble, except that when I did my solo spins, when the rotating ground stopped being a blur, I was looking straight at a RAAF DC-3 (about 3000 feet below me - I started at 9000 feet). THAT gave me lots of adrenalin; the spin didn't.

 

 

[dutchroll]

I never had a Chippy spin go flat from a standard power-off entry. But yes, you certainly needed a fair degree of forward stick to recover. I always moved the stick forward in a controlled manner until it popped out, but I never reached the stops. It was a simple enough matter to centralise controls when the rotation stopped. Even if your head was still spinning, it was pretty obvious when the aeroplane wasn't. The dive recovery could get a bit wonky depending on how quickly you could get your head gyros re-caged! It would be rather nasty to get a washer or other metal FOD stuck in the yoke base!