Landing with one spoiler

At 19:54 28 September 2005, 5z wrote:

Ray Hart wrote:
Having taught your pupils how to get away with this
kind of madness in
what must be a very low performance, incredibly stable/forgiving
two
seater on a huge airfield, do you then brief them
to...

Ray, the whole point here is to show the person that
stuff like this
can be done safely in any type glider. Marty trains
in ASK-21 and I
currently only have access to L-23. But I personally
fly a number of
high performance ships, currently ans ASH-26E and would
have no
problem
trying any of these manouvers in that ship.

What I'm trying to say is that a one spoiler landing
is, to me, a total
non event. But to some is has turned into a fatality.
Why is that?

-Tom

But is that true? One question I mooted had to do
with the effects of
asymetry on a range odd types, especially older, larger
span gliders;
Kestrel19, Jaunus etc. Loss of rudder on a Kestrel
has proved fatal on a
number of occasions, loss of an aileron likewise in
Nimbus 2s, full rudder
deflection on a Janus has to be experienced (but only
at a safe height -
not on final approach). One inevitable problem is
that pilots who die can
not be interviewed to find out what happened, although
they probably
wouldn't know anyway.. I'm still unsure that 'training'
for these events
would prevent more accidents, although the amount of
training prangs
would undoubtedly increase. According to your statistics,
what
proportion of glider accidents have an instructor on
board? If you don't
know, then a little research might be illuminating.

Ray

Ray Hart wrote:

What I'm trying to say is that a one spoiler landing
is, to me, a total
non event. But to some is has turned into a fatality.
Why is that?

-Tom


But is that true?

Any glider can suffer partial control failure from connection problems,
freezing, stick or linkage blockage, undetected damage, mechanical
failures, or improper repairs. I think giving pilots some experience in
these situations with an experienced instructor would be an asset.
Besides the actual skills it might impart, it would make them less
likely to panic in a partial control failure situation. The poster that
thought crashing might be inevitable, even on a Mojave desert sized
airport, comes to mind.

One question I mooted had to do with the effects
of asymetry on a range odd types, especially older, larger span
gliders; Kestrel19, Jaunus etc. Loss of rudder on a Kestrel has
proved fatal on a number of occasions, loss of an aileron likewise in
Nimbus 2s, full rudder deflection on a Janus has to be experienced
(but only at a safe height - not on final approach).

From what you say, it sounds like pilots of these gliders are in
particular need of "partial control" training. Instead of avoiding any
training of this type just because some gliders are troublesome, I think
instructors should be encouraged to provide it because most gliders
_aren't_ like the few you mention. And regardless of the type of glider
a pilot is transitioning to, he should seek out a good briefing on it's
operation, and even take additional training if the glider's quirks
exceed his abilities.


--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

On Thu, 29 Sep 2005 09:17:17 -0700, Eric Greenwell
wrote:

Any glider can suffer partial control failure from connection problems,
freezing, stick or linkage blockage, undetected damage, mechanical
failures, or improper repairs. I think giving pilots some experience in
these situations with an experienced instructor would be an asset.

Hmm... it depends on the type of glider, type of damage, pilot skill,
and luck. I think an airbrake failure is survivable, but any other
kind of primary flight control failure needs a lot of luck to be
survivable.

For example, the seemingly not-so-important rudder:
I once saw a halfways safe no-damage landing of a Twin 2 with a jammed
rudder - but a jammed rudder killed two very experienced pilots in a
DG-500M when they were unable to touchdown in a controlled manner out
of a sideslip.


Basically I think it's not a good solution to find myself slowly
losing control of your glider while on final at 150 ft although I
could have bailed out safely 2.000 ft higher. At least I can blame
myself for trying to be a hero till impact.

My decision for myself is clear: As soon as I'm not absolutely sure
anymore to have the glider under control, I bail out. I have no need
for control experiments at low altitudes where the slightest mistake
is definitely going to kill me - especially if the alternative is a
relatively safe bail-out out of a halfways controlled glider.




Bye
Andreas

Andreas Maurer wrote:


My decision for myself is clear: As soon as I'm not absolutely sure
anymore to have the glider under control, I bail out. I have no need
for control experiments at low altitudes where the slightest mistake
is definitely going to kill me - especially if the alternative is a
relatively safe bail-out out of a halfways controlled glider.


Yes, but deciding when that happens is the hard part, well was for me
anyway. I have had 2 partial primary control failures (in 4 years of
gliding), landed safely each time, but I still wonder if I made the
right decision. The first was in LS4, at about 7000 feet and at that
time I had about 120 hrs in about two years of gliding. It was a rented
ship away from my own club. The ship just had its manual, was test
flown by its owner and I have flown it for 4 days prior to this
incident. I do a pcc before each flight and did it then. The aileron
movement was not the smoothest but I was assured it was OK. Anyway at
about 7000 I needed a large aileron deflection to the right and about
half way there was a definite stop. Stupidly (if automatically) I
applied a fair force and powered through the obstruction. I remember
thinking at the same time something like "you idiot, what if it does not
come back". Well it did come back, I did some testing, the event did
not repeat in a pattern that I could discern, but as the obstruction
only occurred at about half travel so I have decided to land. I have
increased speed to about 70 kts, where only small deflections were
needed and landed normally. I have only recently found out that there
was a serious problem that was rectified.
The second incident happened in my club ship, a Hornet. Once again a
DI, including a PCC was done. I have flown for about 2 hours without an
incident when I went to pull up quite sharply into a thermal when the
elevator come to a full stop with what felt like a soft clunk. Anyway
once again I did some testing and found that with what was a full
elevator I could fly no slower then 55 kts and a bit more with
airbrakes. The controls felt perfectly normal in the remaining range.
Anyway, once again I decided to land. When I descended to about 2000 ft
AGL I put away the air brakes to set up a landing pattern. At stage I
found that I could not fly slower then about 65kts. Anyway, a bit of
adrenalin must have manifested itself at this point and a sharper tug on
the elevator freed the control. I have landed normally. When we
removed the elevator we have discovered a piece of lead ballast in the
tail. It was put in upside down and moved in flight wedging under a
flange on the elevator pushrod (hence the soft clunk).
Clearly a few safety issues here - the use of the ballast was not
universally known by club members, checking for it was not part of the
DI and apart from the control locking there could have been a C of G
problem for lighter pilots. Anyway, these issues have been addressed.

The second incident came about 3 month after the first one and I am sure
both had a significant impact on my flying confidence.

In any case, to this day I am not sure that I have done the right thing
by remaining with the glider. In both cases I had a stable platform to
depart and I have some 100 jumps to my name, admittedly some 30 years
earlier, so I think I would have been relatively comfortable jumping.


Paul

Paul wrote:

In any case, to this day I am not sure that I have done the right thing
by remaining with the glider. In both cases I had a stable platform to
depart and I have some 100 jumps to my name, admittedly some 30 years
earlier, so I think I would have been relatively comfortable jumping.

This is interesting, because some people recommend all gliders making at
least one practice jump, partly on the theory they won't be so reluctant
to jump when they need to. Maybe it's more wishful thinking than good
advice, but I don't know of any "post jump" interviews to see if the
jumpee agreed with the theory.


--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Eric Greenwell wrote:


This is interesting, because some people recommend all gliders making at
least one practice jump,

Make that "glider pilots".



--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Well, I've been making spoilerless landings for years. Of course, the
ships I've flown most don't have them... but I had my smart@$$ hat on
and just couldn't help myself...

Jack Womack

The Slingsby Kestrel 19 is one glider which needs care if sideslipping close
to the ground. The rudder overbalances, and it needs a considerable force
on the rudder to take the sideslip off.

If you have no rudder, how do you get it out of the sideslip once you have
rudder overbalance? I can't think of a way to do it.

One friend of mine had his Kestrel 19 go out of control in yaw shortly after
releasing from aerotow at about 2,000ft. QFE. In fact the rudder had
fallen off, though sitting in the cockpit he did not know this. He baled
out while the glider was flying level though not under full control; I and
everyone else at the time thought he was sensible to do this.

The rudder drive had broken, all Kestrels were modified as a result.

W.J. (Bill) Dean (U.K.).

"Andreas Maurer" wrote in message
...
On Thu, 29 Sep 2005 09:17:17 -0700, Eric Greenwell
wrote:

Any glider can suffer partial control failure from connection problems,
freezing, stick or linkage blockage, undetected damage, mechanical
failures, or improper repairs. I think giving pilots some experience in
these situations with an experienced instructor would be an asset.

Hmm... it depends on the type of glider, type of damage, pilot skill,
and luck. I think an airbrake failure is survivable, but any other
kind of primary flight control failure needs a lot of luck to be
survivable.

For example, the seemingly not-so-important rudder:
I once saw a halfways safe no-damage landing of a Twin 2 with a jammed
rudder - but a jammed rudder killed two very experienced pilots in a
DG-500M when they were unable to touchdown in a controlled manner out
of a sideslip.


Basically I think it's not a good solution to find myself slowly
losing control of your glider while on final at 150 ft although I
could have bailed out safely 2.000 ft higher. At least I can blame
myself for trying to be a hero till impact.

My decision for myself is clear: As soon as I'm not absolutely sure
anymore to have the glider under control, I bail out. I have no need
for control experiments at low altitudes where the slightest mistake
is definitely going to kill me - especially if the alternative is a
relatively safe bail-out out of a halfways controlled glider.




Bye
Andreas

A good approach would be awareness, if one considers actual training too
risky. The Glider Flying Handbook from the FAA has a chapter on Abnormal and
Emergency Procedures. It contains suggested procedures for a wide variety of
system failures, including such things as asymmetric spoiler deployment.
Worth reading... and rereading now and then.