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ratarsedagain
3rd Mar 2003, 12:58
Having just watched the sight of one of the formidable B52's landing at Fairford on the news, just wondered if someone could answer a question for me.
Is the whole lot of it's main gear steerable/castoring, as the one that landed, rolled out down the r/w with the nose pointing about 10-15 degrees off the centreline?
Ta.

Dipole
3rd Mar 2003, 13:09
Certainly can!

I'm not sure of the exact figure but the crab angle can be set in the flight deck

take_that
3rd Mar 2003, 13:13
Anyone any idea what it's max crosswind limit is then?

ratarsedagain
3rd Mar 2003, 13:13
Cheers!
Bloody clever that. Pity my li'l ole 777 can't do it!!!!

TR4A
3rd Mar 2003, 17:07
I'm not sure of the exact figure but the crab angle can be set in the flight deck

About 20 degrees. With those long wings and spoiler roll control you would not want to be doing a wing low crosswind landing.

Volume
4th Mar 2003, 05:59
To make the plane less vulnerable, the B52 uses fully manual controls. (no hydraulic with all the lines that can be shot at)
To limit rudder forces to the pilots capability, the depth of the rudder is just about 10% chord, much to small to handle a crosswind landing without castoring the wheels and touching down crabbed.
The elevator also has some technically very interesting feature, an internal force compensation inside the horizontal tail using the pressure difference between elevator upper and lower surface at the hinge line. The elevators nose is protuding far into the stabilizer and is sealed against it. So the forces on the control surface aft of the hinge are compensated by forces on front of it inside the stabilizer.
Cold war led to some amazing technical achivements in aviation.

greengage22
4th Mar 2003, 07:30
Somebody did tell me once (but I'm not sure if it's true, and I'd like to have it confirmed) that the wheel castoring could be fed from the navigator's Doppler drift, making it fully automatic.

Anyone know if that's correct?

small4
4th Mar 2003, 08:00
As far as I remember the offset is manual only on the B52.

The C5 Galaxy has a similar system which can be tied into the Doppler drift system. A great idea, but I believe it was deactivated after a couple of Doppler drift runaways in the flare leading to a large number of tyre changes at the same time!!!

I'm sure there is someone out there who can confirm or modify this information as it is from some time ago!!!

18greens
5th Mar 2003, 15:51
If the offset is manual how do the crews gauge what to set it at?

Do they have a gauge on the knob that sets it? If they get it wrong (say 15 degrees instead of 20) do the wheels sort themselves out?

oxford blue
6th Mar 2003, 08:28
The nav can read the doppler drift out over the intercomm at, say, 200 feet, and the pilot can set it manually. That way, the nav can check that the doppler's locked on at the time. If it isn't, he still has the ATC surface wind and his CRP5 (or the USAF equivalent).

These days, it's probably available off the INS anyway, because the B52 has had several mid-life updates of the nav and weapons systems. And INS doesn't unlock.