Author Topic: wheels should stop rolling shortly after they leave the ground (Read 922 times)

Citabria · « **on:** November 10, 2003, 10:49:02 AM »

or if the pilot hits the brakes in fligth with gear down

they shouldnt roll when flying and not in contact with the runway

Furball · « **Reply #1 on:** November 10, 2003, 10:56:51 AM »

cc, i tried stopping the wheels with brakes too. Would the tires spin anyway though without brake pressure because of the airflow going over them?

Kaz · « **Reply #2 on:** November 10, 2003, 11:10:12 AM »

Nope they wouldn't and I dare any of you lesser beings to challenge me!! Sorry, temporary megalomaniac complex...

moot · « **Reply #3 on:** November 10, 2003, 12:31:43 PM »

tadpole

mos · « **Reply #4 on:** November 10, 2003, 03:43:23 PM »

Quote

Originally posted by Furball
cc, i tried stopping the wheels with brakes too. Would the tires spin anyway though without brake pressure because of the airflow going over them?

In a word, no. You're right, in that the air flowing over the wheels would cause them to rotate. The problem is, the air flowing under the wheels cause them to rotate equally in the opposite direction. When the plane takes off, the wheels will continue spinning for a bit --they won't just immediately lock when they lose contact with the ground-- but eventually friction will cause them to stop.

jodgi · « **Reply #5 on:** November 11, 2003, 11:55:36 AM »

It is checklist procedure on many aircraft types to tap the brakes before retracting the gear to avoid problems (?) with spinning wheels in the wheelwell.

DamnedRen · « **Reply #6 on:** November 19, 2003, 04:02:15 AM »

Actually there is a wooden block in most planes which act as a "snubber" to stop wheel rotation. It is still used today in the nose gear for most modern jets. The next time you fly somewhere, listen for the thump of the nose gear hitting the snubber on "gear up". It is very noticable.

Ren

RTR · « **Reply #7 on:** November 19, 2003, 09:16:03 AM »

Guess I'm gonna dip into my old Fighter days.
When an aircraft becomes airborne, the wheels are spinning at a considerable rate. Allowing them to continue spinning as they enter the wheel well can have some pretty catastrophic results.

Many aircraft use an anti spin system to stop the wheels from spinning before entering the well. Basically what happens is once gear is selected "up" AND the squat switch is released (or activated depending on the system), hydraulic pressure is applied to the brake system automatically to stop the wheels from spinning, prior to them entering the wheel well. Once "up and locked" the pressure is removed.

Conversly when landing, if the pilot is applying pressure to the brakes before touchdown, damage and/or very premature wear to the tire can result. (due to the fact that the wheel is unable to spin at touchdown). In order to prevent this, many aircraft have an "anti-skid" type system which won't allow hydraulic pressure to act on the brake system until the wheel hits a set rotational speed. (basically allowing the wheel to come up to speed once on the ground, so great chunks of tire aren't ripped off at touch down).

Now, there are other methods used ( REN pointed one out) as well, but these systems I have described are fairly common for larger and/or higher performance aircraft.

Cheers,
RTR

mrblack · « **Reply #8 on:** November 19, 2003, 03:22:32 PM »

friction:aok

Nod · « **Reply #9 on:** November 24, 2003, 11:01:18 PM »

Fester i love reading your posts, they make me laugh:lol

The 109's winsheald is 2cm to small what are you thinking Hitech?????

The wheels still roll when you get off the ground!!!!

The 109's air speed indecator is half a millimeter off, yah need to fix that Hitech!!!!!

The most minute details is wrong and Fester is all over them

i have to say though it is admerable:aok

Citabria · « **Reply #10 on:** November 25, 2003, 04:34:17 PM »

i notice things that no one else does.

its called attention to detail.
HTC is made aware of small details it does not mean they act on them, though sometimes they do.

Nod · « **Reply #11 on:** November 25, 2003, 08:10:53 PM »

well lets hope they act on em.....

~~Fester~~

jodgi · « **Reply #12 on:** November 25, 2003, 08:17:52 PM »

Oh, Nod

U get ignored alot?

Nod · « **Reply #13 on:** November 25, 2003, 09:00:45 PM »

Not really.......

U trying to be an A**?

jodgi · « **Reply #14 on:** November 25, 2003, 09:36:35 PM »

Funny u should ask that...