Auto-Towing - why is this not more popular?

Chapter 3 of the classic American Soaring Handbook has about 23 pages on Auto Tow with several illustrations including a homebuilt car tow release and a technical discussion of the process. 3,500' of runway is the minimum runway length suggested so the sailplane can (barely) make a 360 degree circle to land. Straight-line auto tow and auto tow with pulley are discussed in detail.

As simple as it appears, auto tow should be carefully researched. Finding a sailplane pilot who has supervised auto tow is essential. A ground-launch endorsement from an authorized CFI per FAR 61.31(j) is required for the sailplane pilot unless "grandfathered" however proficiency is essential for both the pilot and the driver. An observer in the auto is important for safety. Density altitude will affect the power of the auto motor and the speed required for the sailplane to launch.

One possible issue with auto tow on airports with airplane traffic is that the cable cannot be reeled in unless a winch system is mounted on the back of a pick-up truck. Some of the hang glider folks have developed this system.

Read the article in the May-June 1955 SOARING magazine, "The Elimination of Guess-Work in Auto Towing" by Otto Zauner and Art Heavener.

The American Soaring Handbook was a binder of 10 chapters on essential aspects that a SSA club needed to know about maintenance, auto, winch and aerotow launching, instruments and much more. Long out of print this handy 6"x9" blue binder might be found on dusty bookshelves in gliderport clubhouses around the USA. Often listed on E-bay and internet book searches such as Albris, this valuable collection of knowledge written by some of the legends of soaring is essential reading. About $25 if all of the 10 chapters are included in the binder.

For an entertaining (but not instructional) video of auto tow watch the "Reunion" episode of the '50's Sci-Fi TV show, "One Step Beyond".

Two excellent posts above from Roy and Burt. I learned partially on auto tow, with maybe 25 launches done by that method over the space of two winters (we would put the towplane away for the winter and revert to auto towing).. Roy summarizes the operational aspects beautifully. As far as equipment, we used "junker" big-block American iron from the early and mid 1970s. The Oldsmobile Custom Cruiser wagon was ideal, since it has a built-in observer seat in the rear. We found that for whatever reason, auto-towing seemed to put a lot of wear and tear on the transition and drive train. Moderately hard acceleration with the load of the glider followed by near-panic stopping repeatedly at the other end meant that I got to be a pretty decent auto mechanic. At our facility, we had 3,000 foot paved with 800 or so grass overrun. With the glider's tail right in the weeds, the car was just on the runway. That gave us the full 3,000 to accelerate, cruise, then stop. We normally got about 600 feet of altitude, though 700 or even 800 was possible if the wind was right down the runway.

So, it's definitely a viable option, especially for early training. Practically, we ended up getting maybe 8-10 launches during a session before something broke on the vehicle or we had a big rope break. We spent a lot of time fixing per every minute of aviating, but when you're in college, $5 tows are attractive!

Erik Mann (P3)

At 11:24 05 October 2015, Burt Compton - Marfa Gliders, west Texas wrote:
Chapter 3 of the classic American Soaring Handbook has about 23 pages on
Au=
to Tow with several illustrations including a homebuilt car tow release
and=
a technical discussion of the process. 3,500' of runway is the minimum
ru=
nway length suggested so the sailplane can (barely) make a 360 degree
circl=
e to land. Straight-line auto tow and auto tow with pulley are discussed
i=
n detail. =20

As simple as it appears, auto tow should be carefully researched. Finding
a=
sailplane pilot who has supervised auto tow is essential. A
ground-launch=
endorsement from an authorized CFI per FAR 61.31(j) is required for the
sa=
ilplane pilot unless "grandfathered" however proficiency is essential for
b=
oth the pilot and the driver. An observer in the auto is important for
saf=
ety. Density altitude will affect the power of the auto motor and the
spee=
d required for the sailplane to launch.

One possible issue with auto tow on airports with airplane traffic is
that
=
the cable cannot be reeled in unless a winch system is mounted on the
back
=
of a pick-up truck. Some of the hang glider folks have developed this
syst=
em.=20

Read the article in the May-June 1955 SOARING magazine, "The Elimination
of=
Guess-Work in Auto Towing" by Otto Zauner and Art Heavener. =20

The American Soaring Handbook was a binder of 10 chapters on essential
aspe=
cts that a SSA club needed to know about maintenance, auto, winch and
aerot=
ow launching, instruments and much more. Long out of print this handy
6"x9=
" blue binder might be found on dusty bookshelves in gliderport
clubhouses
=
around the USA. Often listed on E-bay and internet book searches such as
A=
lbris, this valuable collection of knowledge written by some of the
legends=
of soaring is essential reading. About $25 if all of the 10 chapters
are
=
included in the binder.

For an entertaining (but not instructional) video of auto tow watch the
"Re=
union" episode of the '50's Sci-Fi TV show, "One Step Beyond".
Yep, my dad was the glider pilot and I was the tow car driver . I was
fifteen then. Ross

Ross Briegleb