Rotor strike maintenance actions

By the looks of it, this is both a sudden stoppage and hard landing event. Basically looking at a detailed inspection and replacement. Obviously gonna need a few new / reman blades. I think those go for about 15K apiece. Going to need to inspect all xmsn components. Tail rotor drive shafts, their linkages (flex pack) and alignment hanger bearings will need to be inspected. Engine and gear box mounts inspected. Freewheeling unit sent off for inspection. Engine tear down / inspection with emphasis on the N2/Np shaft and it's gear box. Output shaft to the main xmsn inspected. Mast inspected for alignment. Basically all spinning components on the hub such as the hub itself, lead lag dampers, elastomeric bearings. Then the pitch change links, rotating & non rotating swashplates, scissor / idler links, all inspected.

Some of that stuff can be inspected by an A&P but a lot needs to be sent off to specified maintenance facilities.
 
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What about that vertical shaft the main rotor attaches to? and the hub. Maybe you mentioned those and I don't recognize their names. It must suffer immense torque during stoppage.
 
Let'sgoflying! said:
What about that vertical shaft the main rotor attaches to? and the hub. Maybe you mentioned those and I don't recognize their names. It must suffer immense torque during stoppage.
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Yep, the mast and the hub inspected. I know a guy who had an over torque on a B407 and based on the percentage he hit, the mast was sent off. Came back within tolerance.
 
Depending on the component times and year/model it could possibly be a total loss. Probably have to check the tail boom mounts as well as the rotating components. Not sure what year this is, but the newer, heavier 500’s are susceptible to breaking the tail off or severely damaging the attach points during events like this.
 
So why were they trying to net the elk? Doesn’t appear like they worked for any state or federal government wildlife agency such as DNR, F&W, etc. as the passenger was Australian and the helicopter is privately registered.
 
For this model helicopter...

After tail rotor blade strike, inspect the following:

If equipped with Bendix couplings, remove and scrap couplings.

Tail rotor blades for dents, nicks, scratches or separation of skin.

Tail rotor flapping hinge bolt for damage.

Tail rotor transmission for radial play and run−out of output shaft, cracks in mounting flanges, and chip detector for metal particles.

Remove for overhaul tail rotor transmission if damage is indicated. If equipped with Kamatics couplings:

Perform Tail Rotor Drive Shaft Twist Inspection. Misaligned or missing stripes require removal and scrapping of drive shaft and Kamatics couplings, and an overhaul inspection of tail rotor transmission (Ref. COM).

Remove tail rotor drive shaft and inspect couplings for distortion and cracks; damper, damper bracket and bulkheads for damage.

NOTE: If damage in excess of allowable limits due to blade strike is noted in above areas, continue with following inspections:

Tail rotor drive fork, pitch links, swashplate, hub and pitch control bearing housing for obvious damage.

Upper fuselage and boom tail rotor control linkage.

If tail rotor control rod is damaged, ensure that all rod bulkhead grommets are in place.

Aft frame of tailboom for cracks and boom skin for loosened or popped rivets.

Main transmission chip detectors and transmission lube pump oil filter for metal particles.

Main rotor hub assembly and strap pack assembly for evidence of damage.
 
Based on most of the Youtube videos I've seen, rotor strikes generally don't end well.
 
SkyDog58 said:
So why were they trying to net the elk? Doesn’t appear like they worked for any state or federal government wildlife agency such as DNR, F&W, etc. as the passenger was Australian and the helicopter is privately registered.
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Can’t say anything about the Aussie pax but wildlife folks nearly always use contractors for tagging, collaring, and counting jobs. I’ll leave out a rant on the quality of the studies and just say the work I’ve seen has little oversight. Getting external funding seems to be the main thing.
 
Velocity173 said:
By the looks of it, this is both a sudden stoppage and hard landing event. Basically looking at a detailed inspection and replacement. Obviously gonna need a few new / reman blades. I think those go for about 15K apiece. Going to need to inspect all xmsn components. Tail rotor drive shafts, their linkages (flex pack) and alignment hanger bearings will need to be inspected. Engine and gear box mounts inspected. Freewheeling unit sent off for inspection. Engine tear down / inspection with emphasis on the N2/Np shaft and it's gear box. Output shaft to the main xmsn inspected. Mast inspected for alignment. Basically all spinning components on the hub such as the hub itself, lead lag dampers, elastomeric bearings. Then the pitch change links, rotating & non rotating swashplates, scissor / idler links, all inspected.

Some of that stuff can be inspected by an A&P but a lot needs to be sent off to specified maintenance facilities.
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So you’re saying the Master Caution light probably came through unscathed?
 
I would suspect a total loss...once you find one bent part it tends to get worse as it goes ...components tend to make chips later even with the first inspection being okay...
 
Lachlan said:
So you’re saying the Master Caution light probably came through unscathed?
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Yes. I have not doubt he had a red engine out light and a red low rotor rpm light on the panel...and an annoyingly loud steady or beeping tone going off. ;)
 
Just read the other thread and said the Elk died of its injuries. Bastards. I hope his herd sues the crap out of that company.
 
Doubtful it will be written off. The 369 is a popular and durable airframe. If the operator doesn't wish to repair it, someone will. Most insurance underwriters don't sign off "destroyed" on helicopters like they do on GA aircraft. Unless the airframe is an older outdated version, fire-damaged, heavily corroded, or short on spare availability due to no OEM support, majority of damaged helicopters are repaired and put back to work. Some have gone through that cycle several times and are still earning a living at 25K+ TIS.
 
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