Helicopter Nose wheel steering.

[dieseldo]

I ask this question here because I can only think this might apply to a large military aircraft I certainly have never come across it.

A statement in a set of training notes talks at length about hydraulically powered nose wheel steering similar to a large fixed wing.
Has anyone come across such a system on a helicopter?

My supplementary question concerns the Chinnook, again the same notes talk about one of the rear wheels castering to allow steering on the ground. I would have thought that both would have to caster to stop scrubbing of the tyre on the locked aft wheel. A brief explanation of how the beast steers on the ground would be much appreciated.

Thanks

Dieseldo

[WASALOADIE]

Chinook has hydraulic steering on one of the rear wheels, the other castors. Both can be locked into the fore/aft position. Controlled via a small wheel/knob on the centre consol.

[212man]

Has anyone come across such a system on a helicopter?

Mil-26, for one. I'd guess - but don't know - the CH-53 too

[Harry the Hun]

NH-90 NFH has a hydraulic nose wheel steering, controled with a rotating slider/twist grip on the right collective.

[Rigga]

Puma's have Hydraulic Powered Nose Wheel Steering.

[Bravo73]

Puma's have Hydraulic Powered Nose Wheel Steering.

Super Pumas don't!

[RODF3]

Merlin has nose wheel steering and a castoring facility.

[ShyTorque]

Puma's have Hydraulic Powered Nose Wheel Steering.

Nor do the RAF's HC1s.

[Aesir]

Puma's have Hydraulic Powered Nose Wheel Steering.

:E Hydraulically powered via the tailrotor.

[BTC8183]

The Nosewheel steering[Hyd powered] system was/is an option on, IIRC, certain 'maritime' versions of the AS332L/532.If anyone has a MK1 IPC,it will show the S/N's of those concerned.

[JohnDixson]

212, none of the models have it. Do have a shimmy damper built in. but no power steering like the CH-47.

[212man]

Thanks John - like I said, it was a guess. I'm surprised to see that a 70,000+lb aircraft relies on castoring!

[JohnDixson]

With a 20 ft diameter tail rotor and a large pitch range, pilot has precise and powerful control over taxi heading.

By a coincidence, I think I picked up the first CH-47A delivered to the Army with the left rear wheel power steering. ( tail no 13106, and it had the water landing kit as well-1964 ). Early Chinook drivers will recall the ease with which slightly ham-footed pilots could put in too much pedal for a taxi turn, and deposit droop stops onto the tarmac. The next step involved getting long 4 X 6 lumber and placing it against the fuselage, so that when the blades slowed down during shutdown, they would hit the lumber, rather than taking divots out of the fuselage. ( Major Allen Murphy, are you out there somewhere? ). My recollection is that the flight manual had a ground taxi limit of 3/4 inch of pedal input to prevent this from happening. But what pilots really did was to taxi with the swivel locks in the two aft wheels, and the forward wheels off the ground. Much easier to do, and with some collective applied to get the front wheels airborne, droop stop contact really could not occur.

One can see why the steerable rear wheel appeared on the CH-47.

Over the years, there has been a lot of beer consumed arguing the merits of the 53 vs the 47, but ground handling never comes up!

[stilton]

Ok, scuse the ignorance from a fixed wing Pilot but do Helicopters with wheels not have brakes then ? :)

[Bravo73]

Yep, wheeled helicopters have brakes.

In the most common configuration (one nose wheel, two main wheels), the two main wheels are braked individually, giving the ability to apply differential braking if required.

[dieseldo]

The main difference between a helicopter and a fixed wing in this context is the ability to do a spot turn. You dont want a brake on as it will try to tear the tyre off the rim.

Running landings are not that common so brakes are normally for parking although as has been said diff breaking is available if required.

Thanks to all who have replied to my questions, just goes to show that no matter how long you have been in the industry there is always more to learn. Its what makes it so interesting.