Chutes and Helicopters.
 

No light helicopter that i am aware of, has the extra safety feature of a parachute. If it were acceptable and possible to fit a balistic chute to a Robinson 22, where would be the best position to locate, and which would be the best angle relative to the machine, to deploy the chute. Bug.

Surely the only place that it could be located is the top of the rotorhead? :confused:


Otherwise, you'd have to get the blades stopped before the 'chute could be deployed. And that's not really something that I'd want to do in flight (for all of the obvious reasons!)...

In order to use a parachute, you would have to blow the blades off. The US Army investigated the possible use of parachutes, but the requirement for explosives being in place to blow the rotor head made the system totally unfeasible. Putting a parachute on an airplane isn't that smart, and doing it on a helicopter is simply beyond the pale.

The ATI ultrasport 496 used to have a BRS listed as an option. But it seems to have gone away.

http://www.ultrasport.rotor.com/ultrasport496.htm

-- IFMU

Ah yes....The US Army and parachutes for helicopters!

I was around when the discussion began....and upon hearing the plan involved removing the blades by means of explosive bolts...knowing it would be done by the lowest bidder, maintained by soldiers....well now that posed a few obstacles.

Mind you at the same time we were having problems with the Chinook shedding blades of its own accord....something about the incidence bolts shearing and thus allowing the blade to rotate ninety degrees in the socket.

I always wondered what the odds were all six blades would separate fully and simultaneously without destroying the aircraft.....what an experience that would be even if the system did work.

In those days the TO&E (Table of organization and equipment) for a Chinook company listed one parachute for use during test flights (and totally ignoring the minimum crew being listed as two pilots and a flight engineer).:uhoh:

The good old days!:ugh:

Gomer Pylot,

Have a look at Cirrus Aircraft, there the best selling single engine piston Fixed-wing, They have a system called CAAP's, There is a parachute fitted to the aircraft. I have flown these aircraft and gone through the course as when to use the chute, the system is great. Especially when your S/E night VFR or IFR and can't see !!!! beneath you... pull the chute.. or if you have fixed-gear and your over water...pull the chute... It's a well proven system that has saved many lives and limited damage to aircraft in the event of failure (engine or structural). Not such a stupid idea.

As for helicopters.... who knows... different kettle of fish.

A leathery old geezer once told me...."An ounce of prevention is worth a pound of cure!". He also opined it was wise to walk around a Rattlesnake vice stepping on one.

At a height of 1000ft would a chute deploy in time of the typical fall to earth from a height incident?

How many accidents are of the fall to earth type?

Would it be used if a pilot found themselves in a white out?


How much would such a chute weight?

Mickjoebill

The parachute in the Cirrus is a marketing tool for selling to people who don't know any better, and that's the market the Cirrus folks are after. The only time I would use a parachute would be when the wings come off, and that's not a common occurrence.

I have a pair of Big-Spring shoes for elevator riders, and some poison filters for public water fountains, as well. Those who think so little of the structure of their helicopter that they want a last-chance parachute should stick to riding hobby-horses, and leave flying to the big fellows.

And also taken quite a few.

Nick,

I reckon your theory would suggest the Titanic did not need any lifeboats...or is that taking your proposition in a non-logical manner?

If small flying devices could be fitted that have a total weight of 0.1% of the MGW of the machine (like the lifeboats) than have at it. But if the system needs to blow off the blades, cripple the ability to fly and also weighs 5% of the total MGW, then forget it!

Hughes Helicopters actually looked at a parachute design in the early eighties. The static mast design of the main rotor would allow a parachute to be fitted above the rotor and it would not rotate when deployed. The real problem was the failure mode analysis. Should the chute be inadvertantly deployed by the crew, or should some failure in the design cause the chute to deploy the results in powered flight could be catastrophic. Then there is the matter of an unguided, non-steerable chute with a helicopter swinging underneath. There is the small matter of persons and property on the surface.



The parachute design on the MD500 was not a matter of 'can we' because it was possible to deploy a chute and land at survivable vertical and horizontal velocities; but 'should we'.

Is there a weight breakdown on typical components making up helicopter MGW anywhere? I realise that this will differ for different mission requirements, but have no real idea at the moment. It is something i've long wanted to get a handle on...

If the ballistic chute had a multi-strand cable that could wind up some without failing, and the collective went to full pitch to slow the rotor in about 20 rotations. That might work.

The problem with chutes is they only work from higher altitudes, most problems are near the ground.

I would work on an impact absorbing cockpit.

Slowrotor, they're called oleos and are designed to absorb most of the energy from a full autorotation descent (with seat stroking limiting decceleration). For the mass of a chute you could design the rotorhead to have multiple loadpath structural redundancy. Tail rotors, and associated structure, seem to be the achilles heel.

I believe TPs regularly fly with parachutes. Someone from the EH101 programme may be able to give details of their use first hand.........