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Old September 8th 09, 05:57 PM posted to rec.aviation.soaring
Alex[_5_]
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Posts: 24
Default Double Release Failure

On Sep 8, 7:13*am, FBCompton wrote:
On Sep 7, 11:21*pm, wrote:

**Is anyone teaching this


anymore?


Barry


Sure. *It's a good exercise for proficiency and confidence building.
Touch and goes, taxiing and even turning at runway intersection to
take off on a different runway. *Good communication, experienced tow
pilots, proper conditions, *FUN!


Why all CFIG's (in the USA) must discuss and teach this maneuver: *It
appears in your FAA Practical Test Standards (PTS) for Glider
"checkrides" under the Area of Operation "Launches and Landings"/
"Abnormal Occurrences" / "Glider and towplane release
failure" (meaning both releases fail.) *This is one of five listed
abnormal situations in your FAA PTS. *FAA allows the Examiner to ask
you to perform this maneuver, as the Examiner may ask you to perform
any or all of the tasks under "Abnormal Occurrences." *Most Examiners
just ask for the "towline break" demonstration and the "glider (only)
release failure" signal on tow, but "double release" is part of the
PTS, so be prepared to at least discuss the procedure on your
checkride.

Note to CFIG's: *Just because a double release failure is rare does
not mean you can skip over it in the PTS. * The FAA discusses double
release failure in the FAA Glider Flying Handbook, Chapter 7. *Not
much of a discussion however, but there it is. * Towpilots need to be
thoroughly briefed by a towpilot who has flown this maneuver. *The
descent is very gradual at a proper approach airspeed. *If the
approach doesn't look or feel right, the towpilot has the option to go
around and climb with glider still in tow.

Note to Readers: *My discussion posted here is abbreviated and not
complete and not to be substituted or used for any aspect of your
ground and flight instruction. *This post is discussion, not
instruction.

Regarding the glider in "low tow" position: *Because the towplane is
gradually descending the wake is relatively higher, so the glider does
not need to be too low in relation to the towplane. *The sight picture
is usually not as low as when you box the wake -- just enough to be
just under the wake, and with a full view of the towrope. *Keep the
airbrakes unlocked and deployed as needed to keep a tight towrope at
all times. Overrunning the towplane is the dangerous part both in the
air and on the ground roll out. *Be ready to release.

Important Timing Aspect: *The glider (in low tow) must not touch down
much before the towplane -- this can be a hazardous aspect -- touching
down well before the towplane and stalling it. *The glider wings are
still carrying the weight of the glider while it is flying. *Once the
glider touches the wings stop lifting and the glider creates more
weight drag on the towplane, which if still well above the runway will
be slowed and may stall. *If you try this maneuver, keep the glider
flying until the towplane is about one meter above the runway. *Make
sure the towpilot keeps the towplane moving forward (no brakes) with
some power to help keep the rope tight. *Glider pilot deploys nearly
full airbrake (spoiler) to keep from lifting off again and some wheel
brake, AFTER the towplane is on the ground. *Just roll out and not be
in a hurry to stop. *Both pilots should release if slack rope
develops. *If lots of runway ahead a touch and go is possible. *Long
runways and a good headwind make landing on tow a bit less
challenging. *A long towrope may be a good idea.

For the most comprehensive discussion and training on landing on tow,
along with purposely breaking the towrope, contact Cindy & Marty at
Caracole Soaring in California. *They have developed this procedure to
be relatively safe, and fun.

Remember, I am not your personal Flight Instructor here. *My
discussion posted here is abbreviated and not complete and not to be
used as part of your ground and flight instruction. * For more
instruction in "abnormal occurrences" on tow consult with your local
Certificated Flight Instructor, one who is proficient in landing on
tow. *You, your Flight Instructor, Towpilot, and FAA Examiner must
determine the level of acceptable risk when performing this or any
maneuver. *You decide if you want to fly a "landing on tow", and don't
blame me if you screw it up.


How much runway do you normally consume before both towplane and
glider come to a safe stop? I realize field elevation, density
altitude, wind,
obstructions, type of towplane and glider, are all variables. We have
a 3000ft dirt strip at 780ft MSL
field elevation, but have barbed wire fences to clear at both ends and
a ditch on one end. Is that enough to do it comfortably?