Do you crab or forward slip in X wind landings

On Sat, 25 Feb 2017 23:19:45 -0800, Bruce Hoult wrote:

On Sunday, February 26, 2017 at 1:00:51 AM UTC+3, Tango Eight wrote:
On Saturday, February 25, 2017 at 4:29:42 PM UTC-5, Martin Gregorie
wrote:
On Sat, 25 Feb 2017 13:03:59 -0800, Jonathan St. Cloud wrote:

Do you crab or forward slip landing in x-winds and why? When I was
taught how to fly an airplane the crab method was used when I
transitioned to gliders my instructor emphasized forward slip over
crab.
Years later I have established my procedures, but I thought this
might
be a useful discussion for newer pilots.

Standard UK training, at least when I learnt and I haven't heard any
different from our instructors since, is to crab with wings level on
approach and kick the glider straight just before touchdown. Another
point is that we are taught to do fully held-off landings regardless
of the size and surface of the club field on the grounds that its the
only sensible way to land out, so we should be able to do it well. I
think the two are related because this keeps the wings level while
speed bleeds off and its fairly easy to kick the glider straight as
it settles. If you also manage a neat two-pointer you can award
yourself brownie points as well as knowing that this will help to
keep the glider running straight despite any cross-wind.


--
martin@ | Martin Gregorie gregorie. | Essex, UK org |

What two seater is being used to teach fully held off landings?

I doubt people are doing *fully* held off landings i.e. with the glider
actually stalling on. More likely it's "held off until the glider is in
the same attitude it will have on the ground .. or a tiny bit more" and
then allowed to settle in that attitude. As it slows, lift at that AoA
becomes insufficient to support the glider, but there is never
aerodynamic stall. Maximum AoA / CL is not reached. Once you touch the
ground AoA can not be increased, so lift can't be, so you can't start
flying again (absent a massive headwind gust) and the *objectives* of a
"fully held off" landing are acheived.

Even nose-draggers like the ASK21 have a tail wheel and are landed
main-and-tail or slightly tail first.

The only exception I know is the PW5. I've never seen anyone land a PW5
tail first. We had an informal challenge to do it when we first got
ours. No one managed it.

Good description. I've never flown a PW6, but I have flown a PW5 and
suppose its also near impossible to fully hold off. Of course fully held
off landings work a treat for ASK-13s and T-21s: both have a nose skid.

In my experience my Std Libelle is the hardest glider to hold off for a
nice two-point landing, primarily because the weak airbrakes mean that if
you start raising the nose even slightly early it will balloon, but its
always a nice end to a flight when both wheels touch the floor together.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |