Helicopter Nose wheel steering.
Thread Starter
Joined: Oct 2007
Posts: 62
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From: England
Helicopter Nose wheel steering.
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
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
Hydraulically powered via the tailrotor.
Joined: Mar 2007
Posts: 1,017
Likes: 165
From: Hobe Sound, Florida
Nose Wheel Steering
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!
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!
Joined: Jul 2002
Aviation Qualifications: ATPL(H)
Posts: 3,052
Likes: 56
From: UK
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.
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.
Thread Starter
Joined: Oct 2007
Posts: 62
Likes: 0
From: England
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.
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.
