I once caused a tow car (Jeep Grand Cherokee) with pulley on the bumper and
rope staked down at mid field to lose traction during taping of an episode
of "Secrets of Speed" for ESPN. We were launching my LS-6a for the opening
shot. Of course the upset is not shown in the aired program, but I have the
raw footage... Emerson Fitipaldi was riding shotgun in the Jeep and he
reached across and took control from the driver.


"Bill D" wrote in message
...
On Oct 18, 6:28 pm, Martin Gregorie
wrote:
On Tue, 18 Oct 2011 06:28:45 -0700, Andy wrote:

As I said in my first answer "if the climb profile was flown correctly".
Auto tow does not require an aggressive climb profile to reach maximum
altitude as long as the runway length is not limiting. Unlike winch
launching the rope length remains constant.

To me, auto-launching on a 200 ft rope sounds uncomfortably like aero-
towing on a CG hook except that now you're *trying* to get above the
'tug'. This sounds to me like a recipe for getting into the
uncontrollable sling-shot region that upsets tugs. Further, it seems to
me that if you do that to a rear-wheel drive vehicle your problems will
be compounded by a loss of acceleration due to loss of traction as the
rope tension reduces the weight on the driving wheels.

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

Yep, but so far as I know, no one has yet upset a tow car. If the
rear end is light, the rear wheels can spin on low traction surfaces
but the solution is to fill the back end of the tow vehicle with
rocks.