Hypothetical Scenario #2 - Urgent Action required

On Sat, 08 Feb 2014 11:05:21 -0800, OneTango wrote:

This is a voluntary pop quiz.

You're circling in a 30 degree left bank at 3000 AGL.

You hear a sudden change in the relative wind. Both rudder pedals go to
the floor. The yaw string is not straight.

One of the rudder cables has broken.

Sub-scenarios:

2A The yaw string points to the right pedal (adverse yaw to the left)

The left cable broke, giving full right rudder. With the stick centred,
the glider should skid right, causing the left tip to rise and, if
uncorrected, the glider should eventually start a skidding right turn. It
may be possible to fly straight with judicious use of left aileron. If
straight flight is possible and a suitable field is in gliding range,
than by thinking well ahead and using the ailerons carefully, it should
be possible to fly a wide pattern and land in the field. If straight
flight is impossible, which may be the case if the glider has a powerful
rudder and you didn't loose more than 2-300 ft finding out, jump out.

2B The yaw string points to the left pedal (adverse yaw to the right)

The right cable broke, applying full left rudder. It may be possible to
straighten out with stick centred or a small amount of right aileron - be
careful or adverse yaw may merely tighten the turn. If the turn shows
signs of tightening, jump out before height loss becomes significant or
speed and G forces build up.

------

If my right foot comes off the pedal in an aircraft with a raising panel,
e.g. an ASK21, I won't get it back on the pedal. In consequence I have
practised rudderless turns, with an instructor, in an ASK-21 and am
confident I can line up for an into-wind landing in a glider with similar
rudder power and stability. As a consequence I will not fly an ASK-21
solo.

I have no such problems in my Libelle, the club's G.103, Juniors or
Puchacz. I think there's a reasonable chance of flying straight with full
rudder in the Libelle, Junior, G103 or ASK-21 but not in the Puchacz
unless its huge rudder would tend to blow straight.

AFAIK none of the gliders I usually fly and have listed above have
springs that would hold the rudder hard over if the cable broke, so
another approach would be to hold your feet clear of the pedals
(difficult in some gliders, plant your heels on the pedal pivots or slide
the pedals right forward. If this works, then you can fly wide,
rudderless turns provided you didn't spin the glider in the mean time.


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