US Government Study on Helicopter Bird Strikes

[SASless]

This link will take you to a study done by the US Government on Helicopter Bird Strikes.

Some sobering facts jump out at you while reading this paper.

helicopters accounted for only 0.6 percent of all bird strikes, helicopters accounted for 13 percent (2) of the 16 aircraft destroyed and 24 percent (34) of the 141 injuries caused by bird strikes (

One would have to conclude helicopters are woefully under designed against bird strikes.

As was posted in the Bond Accident thread....are we aiming at the minimum standard required by the regulating agencies?

Is that the best we can do?

http://www.birdstrike.org/meetings/2006_papers/Dolbeer_helicopter.pdf

[flyer43]

Sobbering thoughts indeed!
From the same para as quoted by SASless:-

Of the 370 reported bird strikes involving helicopters, 186 (50%) indicated damage and 67 (18%) indicated substantial damage. In contrast, only 15% of bird strikes with all aircraft types resulted in damage and 4% resulted in substantial damage.

And from the subsequent para:-

Sixty-three percent of the bird strikes to helicopters and 77 percent of the damaging strikes occurred during the en-route phase of flight. In contrast, only 2 percent of bird strikes and 7 percent of damaging strikes for fixed-wing aircraft occurred during the en-route phase.

The higher rate of en-route strikes on helicopters is no doubt related to the lower flight regime of helicopters. However, it does serve to highlight the fact that helicopters are substantially more prone to birdstrikes and that the damage received is likely to be far more devastating than for fixed-wing.

Although regulators set standards which are intended to provide acceptably safe opperations, it is up to operators and their clients together to ensure that best practises are put in place to reduce the risk to passengers to ALARP - as low as reasonably practicable.

[SASless]

Also.....you notice the study was done by the "Fin and Feathers" folks and not the FAA or NTSB who are charged with Aviation Safety!

Helicopters get one Kilo birds.....errrr....the AB139 and S-92 do.

Sec. 29.631 - Bird strike.

The rotorcraft must be designed to ensure capability of continued safe flight and landing (for Category A) or safe landing (for Category B) after impact with a 2.2-lb (1.0 kg) bird when the velocity of the rotorcraft (relative to the bird along the flight path of the rotorcraft) is equal to VNE or VH (whichever is the lesser) at altitudes up to 8,000 feet. Compliance must be shown by tests or by analysis based on tests carried out on sufficiently representative structures of similar design.

The FAA requires airliners to withstand strikes from birds weighing as much as 8 pounds at particluarly vulnerable points along the aircraft. Kevin Poorman, a senior research engineer at the University of Dayton Research Institute in Ohio, tests the abiltiy of airplanes and engines to withstand bird strikes by firing 4 to 8 pound birds at strategic points along aircraft from coompressed gas guns at hundreds of miles per hour.

[mickjoebill]

If a super tough cockpit material were available what is the likelihood of the bounced bird then causing damage to rotors or engine?

One wonders what percentage of injuries involed pilots not wearing helmets?



Mickjoebill

[SASless]

A very good article on Birdstrikes.....

When Birds Strike - Vertical Online (http://www.verticalmag.com/control/news/templates/?a=11072&z=11)

[birrddog]

Never mind the cockpit, or the air intake, what about the rotor?

I have dodged a bird or ten in my (limited) time where I had little advance notice that it had ceased to be a hawk but a kamikaze dive bomber heading straight down towards the disc.

Some of the kamikaze birds of prey I encountered, I would gather were heaver than 2.2lbs...

Even on a 206 or a 407 I recon that would ruin my day... It certainly did my underwear. :eek:

Any suppositions here what would happen to the rotor at 130kts if hit by a diving bird of prey?

[ShyTorque]

From my own experience, the bird will be splattered and the rotor will not.

My worry is of getting a faceful of bird and pieces of broken plastic windscreen.

[Gomer Pylot]

I've hit several seagulls with the rotor, mostly at low or zero airspeed, and never found any damage at all. The strike is taken almost entirely by the spar, not the airfoil, because even at a hover it's traveling at a large percentage of the speed of sound at the tip, and it simply disintegrates the bird. At cruise airspeed, the blade is moving only a small percentage faster on the advancing side, and a small percentage slower on the retreating side. I've hit birds at almost every possible location on a helicopter, and IME the blade is the best possible place to hit one.

[Heli-phile]

Most my Helicopter operations are along coastlines or over water, Usually between 800' to 2500' - right amongst our feathered friends!!. Consequently I have had lots of near miss incidents with birds. I soon realised that EVERY bird will dive as soon as it see's you (if it sees you) Consequently I have developed some simple rules
NEVER fly in proximity to landfill/rubbish/trash dumps - This is seagull central!!
Always fly upwind of cliffs/ridgelines, Gulls love soaring here (as well as hang gliders)
Beware Large flocks on beaches, you spook them and up they come!!
Always do a cyclic climb to avoid birds They ALL dive when scared, it also means they hit your belly and not your screen!!!
Get some strobes!! if not, always have your landing light on!! (Yes I know they are expensive bulbs but thats still cheep compared to a bird strike)
Beware albatross's - They are BIG MoFo's and they arent always skimming the waves!! I found one at 1200' once (it actually had a surprised "look" on its -"face"??)

Im sure these tactics + strobes/landing lights have saved a good many impacts/mess/paperwork (or worse!!)

Other tips anyone??

[ChopperFAN]

So how do helicopter tail rotor setups take birdstrikes?

Ive seen a pic of testing with what i think was a BO105.

Just curious as any collision there could damage vital components, would it remove the tail box easily?

Thanks :ok:

[eivissa]

I once hit a seagull in a R44 Clipper at about 100kts while approaching a coastal airport. There was absolutely no time to react. I just spottet a white dot in the blue sky and next thing was the impact sound. The cockpit glass absorbed a lot of the energy and didnt take any damage at all. While still flying I thought that all went quite well, but after shutdown I found out that the bird made a big dent into the rotor mast cowling after bouncing of my cockpit window. If you had seen the mast cowling you would think that RHC calculated the Vne so that incoming air wont deform that part of the chopper. It looked like crumpled paper.