Is this possible?

March 2, 2006

A CFI friend of mine told me this story a while back, he heard it from someone else, (it supposedly took place in Canada- but we have had no luck in verifying IF it indeed realy ever happened) Ths story begins when the machanics were finishing up re-assembling the rotor & installing it back on a 206. They had worked all day & most of the night to get it finished, & decided that after they had got it hoisted back on the top of the helicopter, they would come back early in the morning & finish it up. Well you can imagine their surpise when they walked in the hangar, the helicopter no-where to be found & the retaining nut (jesus nut as some call it) AND the locking hardware were STILL on the bench were they had left it last night ! They ran into flight ops to find out where the ship was,,, "oh the 2 pilots showed up about 1/2 hour ago & are on a flight with it" they were told. Panic didnt take long to set in, as they explaind to flight ops,,,,,,,,,,,After a brief discussion, they all agreed to call the pilots on the radio, But? WHAT do ya tell them to do? The story didnt have a happy ending as i recall & both pilots were killed & the ship was totalled. Did any one else ever hear of this? and?! what would be your reaction to just being told that the key component for the safety of your flight was still on the bench & never installed?

We discussed if this was at all possibe, & (altho neither of us were willing to give it a try) we concluded that it could be possible, as long as once pitch was applied so was ALOT of torqe to keep the trunnion on the mast. Also we discussed what must have gone thru the pilots minds,,,, 1) "flight ops, you ARE sh***ing us, RIGHT?!" 2)" I thought YOU checked THAT !" 3) "whatever we have done to get us up here, DONT change a thing"

tx'd rotors · March 2, 2006

Yeah, we've all heard this story, apparently it's true. Fing crazy though. Good pre-flight goes along way!

Vaqueroaero · March 2, 2006

I recall reading about this in a publication from Bell, so yes it's true. If I remember correctly they flew for about 20 minutes before the head came off.

Also, if I remember right, it was a pilot and mechanic who died as they were on the test flight for the return to service. I don't think anyone talked to them on the radio either.

Sad, but true.

67november · March 2, 2006

"(jesus nut as some call it)" yes we call it the Jesus nut, 'cause that's the first person you're talking to when your fan departs.

delorean · March 2, 2006

Yeah, that happened. It was in Bell's ADHeliPROPs a few years ago. There was a long description of how the assistant was told to paint the nut, then his lead had him do something else, and so on.

Yes, two were killed. The pitch links held the rotor on until they passed through about 75-100 ft, then they departed the aircraft.

flying high · March 3, 2006

Yes,it did happen.I actually have a copy of the report. A very unfortunate accident. All AME's were present at time of take-off ,The rotor hub was obviousy not included in the preflight .Basically everyone assumed everybody else did their part inspections, assembly etc... The lesson here never ASSUME! anything.and always do a good preflight especially after maintenance inspections and service. I wont say where or who but a guy I know was preflighting a bird that just came out of maintenence and found the tailrotor was reassembled backwards ,oops!

joker · March 3, 2006

Yep, reiterating what Flying High said, my best inspections are done after mechanics have been at the aircraft. I wholly respect mechanics, but everyone makes mistakes, and as was shown in the above example, sometimes the system (or lack of system) will not protect you.

From what it seems, there was a breakdown in procedure or several breakdowns in procedures.

Very sad, very silly and avoidable.

Joker

March 3, 2006

Here is a similar story, altho this one has a happy ending. Military pilot had the habit of "requesting" that his crew chief do his pre-flights for him. The crew chief knew that the pilot should be doing at least some of this on his own, so one day as the crew chief was standing in front of the ship as the pilot was spinning up getting ready for departure, he starts tossing the jesus nut up from one hand to the other & waving at the pilot. Pilot immediately shuts the ship down, runs to the crew chief & starts cursing & yelling for letting him get that far into the start procedure knowing that the nut was missing. Crew chief pointed to the nut on the mast that was installed, while still tossing the "spare" from hand to hand. Needless to say, the pilot had learned his lesson the easy way.

I even had a similar situation happen to me one day while i was helping a friend of mine track and balance a 300. ( we were both pilots AND mechanics) After we were satisfied w/ our work, ( i was running the balance equipment, he was doing the flying) Tom got the job of taking off the bracket for the accellerometers and mag-pickup while i wound up the cables & removed the equipment from the cockpit & put it away. By the time i had my job done, Tom had layed his parts on the bench & i put them in the case & we were done ! Inoticed he was on the phone & the ship was on the grass & needed to be flown off the grasss back to the pavement near the hangar, & informed him of my intentions, (he told me to take it around a few times & see what i though w/ the lighter weight ( as he is a BIG boy). I got the thing up into a hover, felt pretty good i thought, and since i had spent the better part of the day sitting in the thing i decided i was too tired to go take it around & landed in front of the hangar & put it away. I usually do a quick "post-flight" at the end of the day too, however since i did a pre-flight that morning & we were flying it most of the day?--- i failed to check Tom's work & do another pre-flight. When i climbed up on the rotor, i noticed one of the nuts was missing on one of the control rods (where the mag-pickup bracket attaches), this was the fore/aft cyclic control rod ! & the lateral rod still had its nut, but only finger tight. While Tom was still on the phone i ran in & said "you trying to kill me?" He had got called away by the phone b4 he finished his job & just assumed i wouldnt fly the thing w/ out checking everything, & i assumed he wouldnt tell me to go fly it w/out it being finished.

I usually try to make situations like this impossible to come about, but? even still everything needs to be checked & re-checked ( preferably NOT by the same person too, i have checked my work at times over & over again, only to find later on i missed something)

Vaqueroaero · March 3, 2006

Two things:

The word ASSUME makes an ASS out of U and ME.

When moving/doing anything with aircraft leave your cell phone alone until you are finished.

I witnessed a guy putting his Jetranger into his hangar, which was a real squeeze. He was busy yapping on the phone and started to close the door down. Sadly he had not got the aircraft into the proper position and the blade was still out too far. The door came down on the blade. It is amazing how much they flex. After much yelling on our behalf he saw what was going on and stopped it. Luckily for him no damage done.

toxedo_2000 · March 6, 2006

Yeah, we've all heard this story, apparently it's true. Fing crazy though. Good pre-flight goes along way!

This story is true. The mecanic was my mecanic, and the pilot was the instructor in chief at the school were I had my flying lessons in Beloeil, Qc. That 206 had been completely rebuilt. One of the other mecanic took off the Jesus nut to paint it. The two guys took off unaware of that fact. They were supposed to check the vibrations or something apparented to that. In flight, when the collective was pushed down, the whole rotor came off and cut the 2 guys in the cabin. The 206 took on fire after falling on the ground. We lost 2 friends in that accident, and a dam good pilot, and a dam good mecanic.

Toxedo

Bladed Sun · March 6, 2006

I'm not sure how it's done in the civilian world but, we have a lot of paperwork that follows any work we do. You go step-by-step : Remove one nut, write it down; remove bolt, write it down; and so forth. Everything gets inspected before you put it back on and the Technical Inspector watches you put it on and write it down. All the while, refering to the tech manual. Of course, being human, mistakes happen. That's why it's called a pre-flight.

My experience happened when I was getting ready to fly an R-22 back to my flight school after a 100 hr. I found a screwdriver under the cowling. Lesson learned early and easy.

Cheers