View Single Post
  #9  
Old October 17th 20, 05:01 PM posted to rec.aviation.soaring
Kenn Sebesta
external usenet poster
 
Posts: 48
Default Wheel brake effectiveness standards

On Saturday, October 17, 2020 at 10:29:03 AM UTC-4, AS wrote:
I flew my club's B4 a bit and as far as I remember, the wheel brake was actuated by a bike-brake type handle on the stick, so one didn't have to release the spoiler handle.


If you think about the ergonomics of that handle, you need to release pressure on the airbrake handle in order to open your hand and warp your fingers around the wheel brake lever. It's extremely unergonomic to actuate the two at the same time with any degree of precision, which is what leads me to believe that they didn't really design the system to have great braking performance. It strikes me more like an afterthought, something they threw in so that we could control how far we roll once we're below 10km/h.

The old Schleicher gliders Ka6, Ka8, etc. had a 'steel band over the tire' brake, which worked ok in dry conditions but were useless on wet grass, yet they were certified gliders. IIRC, the POH called it an 'emergency' brake, i.e. only use them if you are about to go through a fence.


This is a great data point!

I would call 'locking up the wheel at touchdown-speed and MTOW' the upper spec limits of any requirement.


Immediately on touchdown there's very little force on the wheel because most of the plane's weight is still carried by lift. Do you mean that you should be able to lock it up at any point during touchdown?