Recognizing and reacting to tow plane engine failure

On Saturday, October 25, 2014 10:16:38 AM UTC-5, Evan Ludeman wrote:

Dumping the glider because the *rudder* hit the stop is way over the top. Someone needs to HTFU.

What about a situation where the tug's vertical tail stalls due to the glider being way off to the side? If you are holding full rudder against the yaw, and the glider keeps on pulling the tail, you may stall the vertical tail - supposedly the ensuing snap roll is highly entertaining!

This situation may be more theoretical (I think the BGA had an article that mentioned it) but my technique is to let the glider pull my tail around if he really wants to. Unless wake boxing is prebriefed, I pretty much stay off the rudders and let the glider take me where he wants, if he gets out of position laterally.

Kirk
66

On Saturday, October 25, 2014 12:02:56 PM UTC-4, kirk.stant wrote:
On Saturday, October 25, 2014 10:16:38 AM UTC-5, Evan Ludeman wrote:

Dumping the glider because the *rudder* hit the stop is way over the top. Someone needs to HTFU.

What about a situation where the tug's vertical tail stalls due to the glider being way off to the side? If you are holding full rudder against the yaw, and the glider keeps on pulling the tail, you may stall the vertical tail - supposedly the ensuing snap roll is highly entertaining!

This situation may be more theoretical (I think the BGA had an article that mentioned it) but my technique is to let the glider pull my tail around if he really wants to. Unless wake boxing is prebriefed, I pretty much stay off the rudders and let the glider take me where he wants, if he gets out of position laterally.

Kirk
66

The release is there for real emergencies. 99+% of the time, the rudder hitting the stop momentarily is *not* an emergency.

T8

It all happened at 100ft, no mans land for a return to the airfield for the glider.

It's not unusual to hit the rudder stops on takeoff at Moriarty since
we're famous for winds (usually cross winds). That doesn't bother me at
all as long as the trend of the takeoff is good. When I start reaching
for the release is when the nose of the tug slews uncontrollably in any
direction and any of the controls have reached the stops. That happens
when newbies are practicing boxing the wake, but that's been pre-briefed
so I tolerate that.

Dan Marotta

On 10/25/2014 9:16 AM, Evan Ludeman wrote:
On Friday, October 24, 2014 4:46:13 PM UTC-4, Bruce Hoult wrote:


Around here, if a tow pilot hits the stops on any control (including
rudder) then you're going to wear the rope.
Dumping the glider because the *rudder* hit the stop is way over the top. Someone needs to HTFU.

T8

On 2014-10-25 10:54:55 +0000, Cookie said:

When I used to do a lot of "scenic glider rides" many times the
passenger would request to "fly over their house"..but the request was
made once airborne...

Steering turns worked great for this!

Pawnee climbs steeper than the DG1000 descends, so for any given
distance from the airport (other than straight over the boundary fence)
I can fly over lower in free flight than on tow. Especially with a bit
of a dive and then pull up.

I once did a fly by the living room window of a trial flighter who's
house was on a 500 ft ridge 2 miles from the airfield. I would be
nervous there at 50 knots, but with the climb after a pass at 100 knots
it was always going to be fine.

Licensed in 1978, a total of one tow plane engine failure.

I was flying a single seat glass ship with a CG hook. At about 700 ft agl, I inexplicably became high on the tow plane. I slipped and pushed the stick forward, but continued to get even higher!! The first thought through my mind was that the elevator was disconnected, but quickly realized that I was not high on the tow plane, the tow plane was low on me, and quickly getting lower. I released, announced "Glider away, taking the grass". The tow pilot responded "Thanks". We both landed with no problems.

It took about 2-3 seconds after I realized I was high to recognize there was a serious problem and respond to it by releasing. I had always assumed that in case of engine failure, that I would find myself over running the tow plane, or at least, there would be a lot of slack rope. Not so in this case. The only hint I had was the height difference - no slack rope, no black smoke, no engine parts flying back at me, no emergency call from the tow pilot, nothing.

P9

On 2014-10-25 10:52:02 +0000, Cookie said:

Soooo..when practicing "box the wake" one should expect there is a good
possibility to be "given" the rope. ??

Cookie



On Friday, October 24, 2014 4:46:13 PM UTC-4, Bruce Hoult wrote:
On 2014-10-24 16:43:23 +0000, Waveguru said:


Glider pilots and tow pilots have an iron-clad covenant that should be
talked about, not just silently acknowledged: You do your very best
not to kill me, and I'll do my very best not to kill you. Towing is a
unique thing in aviation, it's serious business, and it needs to be
constantly recognized as such.


I had a tow pilot get mad at me just the other month for doing a
steering turn. He slammed the Pawnee over so hard I couldn't follow
him and it broke the rope. My passenger was so freaked out he'll never
fly again. When I talked to the tow pilot about it he admitted that it
****ed him off when I tried to steer him.
Boggs

Around here, if a tow pilot hits the stops on any control (including
rudder) then you're going to wear the rope.

If you want him to turn, use the radio.

If boxing the wake causes the towplane to reach control stops then you
are doing it WAY WRONG and should expect to wear the rope, yes.

Ok...and signalling a turn by moving out to the side will not make the towplane hit its rudder stops either ...so what's the problem?


Shall we now replace all 17 of the "standard American soaring signals"...with "use radio"?

Cookie


If boxing the wake causes the towplane to reach control stops then you
are doing it WAY WRONG and should expect to wear the rope, yes.

On 2014-10-26 09:45:47 +0000, Cookie said:

Ok...and signalling a turn by moving out to the side will not make the
towplane hit its rudder stops either ...so what's the problem?


Shall we now replace all 17 of the "standard American soaring
signals"...with "use radio"?

Cookie


If boxing the wake causes the towplane to reach control stops then you
are doing it WAY WRONG and should expect to wear the rope, yes.

If it's mere communication ... like wagging your wings ... that's one
thing. If it's physically pulling the tail around against the tow pllot
attempting to maintain his intended heading then that's quite another.

On 2014-10-26 09:45:47 +0000, Cookie said:

Ok...and signalling a turn by moving out to the side will not make the
towplane hit its rudder stops either ...so what's the problem?


Shall we now replace all 17 of the "standard American soaring
signals"...with "use radio"?

Cookie


If boxing the wake causes the towplane to reach control stops then you
are doing it WAY WRONG and should expect to wear the rope, yes.

Btw:

Pawnee wingspan 36 ft 2 in. So out at his wingtip you are 5.5 m off
center. On a 60m rope that's 5.3 degrees angle on the rope.

If the glider weighs 600 kg and has a 30:1 L/D at towing speed then
there will be 20 kg of pull in the rope from drag, plus (at 600 fpm, 3
m/s climb and 70 knots 38 m/s airspeed) another 48 kg pull from
climbing. Total 68 kg. About 6 kg of which will be sideways pull on the
tail.

Anyone want to figure out how much rudder deflection it takes to
produce 6 kg sideways force at 70 knots? It won't be a lot.