tow rope brake practice crash, what can we learn...

Students learn several very valuable things during a simulated rope break.
1. they have (at least) a 3 second "oh, ****", factor where they don't
do anything until the reality sets in. I had one student that froze and
did nothing at all.
2. they don't get the nose down fast enough, far enough - even after
they recognize and react to the situation.

As others have pointed out, you have to be careful. On a hot humid day
when you're still far away from the airport at 200, the exercise might
best be postponed. I've found that on a normal day, a rope break at 275
(which is what I typically do)or so gives you an extra margin of safety
and still gets the point across - and spoilers will be needed to not
over-run the airport.

Tony

On 7/11/2011 10:05 PM, Tony V wrote:
Students learn several very valuable things during a simulated rope break.
1. they have (at least) a 3 second "oh, ****", factor where they don't
do anything until the reality sets in. I had one student that froze and
did nothing at all.
2. they don't get the nose down fast enough, far enough - even after
they recognize and react to the situation.

Forgot point number 3. You can't just point the nose down and start your
turn back to the airport. You have to wait until you have enough
airspeed to pull that off. Something that gets drilled into every winch
student (I hope).

Tony

I always teach a multitude of tow failures to pre-solo students
ranging from turn backs at low-ish altitude to abbreviate patterns at
mid altitude to full patterns once high enough. I always sort of grin
when people call it a "simulated rope break". There is nothing
simulated about it! Frankly i find it the most stressful sort of
training that i've ever given because it requires an incredibly high
level of oversight and everything has to be done just right, there
isn't a lot of room for error. I've had a few exciting
ones...probably earned a few early gray hairs as a result.

The more downwind turnarounds i've done the more I realize that in
reality at the airports I usually fly from a landing straight ahead
into the wind off airport is probably at least as safe if not safer
than turning back. I always make sure that my students are not
married to the idea of having to make it back to the runway too. IMO
there is a pretty narrow window of wind/temperature/takeoff
performance and however many other factors that make turning back the
truly best all around option. Remember this is me flying out of
midwest runways with miles of landable fields off the departure ends.

I usually enforce a basic three step process after the rope "breaks".
1: nose down 2: turn (if you need to) 3: land. Lots of pilots forget
#1.

I've also learned over the years that sometimes the most difficult tow
failures are the mid altitudes where you have multiple options
(especially if there is more than one runway at your airport). could
make a short pattern and land into the wind, could pick another runway
for a crosswind landing, could land downwind. sometimes options are a
bad thing and people wait too long to make a decision and then they
are out of options and ideas.

On Jul 11, 7:11*pm, Tony V wrote:
On 7/11/2011 10:05 PM, Tony V wrote:

Forgot point number 3. You can't just point the nose down and start your
turn back to the airport.

You have to wait until you have enough
airspeed to pull that off.


Why? If the simulated break is made at normal tow speed there is
sufficient speed to start the turn immediately.

Andy

On 7/12/2011 12:41 PM, Andy wrote:

Forgot point number 3. You can't just point the nose down and start your
turn back to the airport.

You have to wait until you have enough
airspeed to pull that off.


Why? If the simulated break is made at normal tow speed there is
sufficient speed to start the turn immediately.

Because most students don't start the turn immediately. Tye typical
reaction time is 3 seconds - with the nose high. The nose pointing down
does not necessarily mean that you can turn safely is all that I'm saying.

Tony

On Jul 13, 11:36*am, Tony V wrote:
On 7/12/2011 12:41 PM, Andy wrote:

Forgot point number 3. You can't just point the nose down and start your
turn back to the airport.

You have to wait until you have enough
airspeed to pull that off.

Why? *If the simulated break is made at normal tow speed there is
sufficient speed to start the turn immediately.

Because most students don't start the turn immediately. Tye typical
reaction time is 3 seconds - with the nose high. The nose pointing down
does not necessarily mean that you can turn safely is all that I'm saying..

That's far too long a reaction time and can surely be reduced.

The nose pointed up doesn't mean you can't turn safely. A typical
glass glider with 40 knot stall being towed at 65 - 70 knots can do a
chandelle[1] to accomplish the turn, for heaven's sake!

Stall/spin isn't about nose attitude, it isn't about speed, it's ALL
about stick position.

[1] "wing over" to USians I think -- I don't mean hammerhead/stall
turn.

On Jul 12, 12:41*pm, Andy wrote:
On Jul 11, 7:11*pm, Tony V wrote:

On 7/11/2011 10:05 PM, Tony V wrote:

Forgot point number 3. You can't just point the nose down and start your
turn back to the airport.
You have to wait until you have enough
airspeed to pull that off.

Why? *If the simulated break is made at normal tow speed there is
sufficient speed to start the turn immediately.

Andy

Better response that I teach is to promptly establish the required
gliding attitude, which will no doubt be somewhat mor noe low than
attitude on tow.
UH

On Jul 11, 8:11*pm, Tony V wrote:
On 7/11/2011 10:05 PM, Tony V wrote:

Students learn several very valuable things during a simulated rope break.
1. they have (at least) a 3 second "oh, ****", factor where they don't
do anything until the reality sets in. I had one student that froze and
did nothing at all.
2. they don't get the nose down fast enough, far enough - even after
they recognize and react to the situation.

Forgot point number 3. You can't just point the nose down and start your
turn back to the airport. You have to wait until you have enough
airspeed to pull that off. Something that gets drilled into every winch
student (I hope).

Tony

Actually a 200 foot AGL rope break on a winch is probably safer since
the landing will be straight ahead on the runway. There have been
accidents where aero tow trained pilots turned back from a 200 foot
winch rope break only to find no runway to land on. Of course, both
aero tow and winch recoveries from 200' rope breaks require a fairly
high level of stick and rudder skills.

Hint to students, if your instructor has his head stuck out of the
side window of a 2-33 looking back at the runway, he's probably doing
a 'sanity check' before pulling the release. Sanity checks are highly
recommenced as it's not always possible to return to the runway.

A bit of history; the 200' rope break turn back maneuver was invented
in the early 1960's to show aero tow operations from short runways
surrounded by trees or other unlandable terrain was 'safe'. Since one
can't know what runways a student will fly from in the future,
training them in this maneuver makes sense.

On Jul 12, 3:11*am, Tony V wrote:
snip

Forgot point number 3. You can't just point the nose down and start your
turn back to the airport. You have to wait until you have enough
airspeed to pull that off. Something that gets drilled into every winch
student (I hope).

Interesting. In my own glider a typical tow speed is somewhat above
best l/d speed so the first things would be to lift the nose slightly
and trim for approach speed. It's a typical 15m unflapped glass
glider so 60 knots is fine, typical tow speeds are 70-80 knots.

On Jul 13, 3:01*am, Cats wrote:
On Jul 12, 3:11*am, Tony V wrote:
snip



Forgot point number 3. You can't just point the nose down and start your
turn back to the airport. You have to wait until you have enough
airspeed to pull that off. Something that gets drilled into every winch
student (I hope).

Interesting. *In my own glider a typical tow speed is somewhat above
best l/d speed so the first things would be to lift the nose slightly
and trim for approach speed. *It's a typical 15m unflapped glass
glider so 60 knots is fine, typical tow speeds are 70-80 knots.

Yes, tow speeds are usually greater than approach speeds.....this
means simply that you have "energy" in speed....

In practice at altitude, we often make a 180 degree turn off of tow,
with no loss of altitude.....and just a slight loss of speed...as you
say, staying at or above best l/d speed..We can even do a gently
climbing turn off tow, at altitude, and gain maybe 100' while slowing
from tow speed to best l/d or even slow to min sink. But I would not
recommend this near the ground.

Another point to consider, the faster the speed in a turn, the larger
the radius of turn......there may be some benefit to a slightly slower
turn (but not too slow).

We know that angle of attack is the concern in stall avoidance....any
stall spin accident off of low rope break has to have had too much
angle of attack, one way or another....This means too much stick back
pressure....This is why I like to see an obvious stick forward and
nose pitch down reaction upon rope break.....also smooth control
inputs....

But speed (suffecient speed) is also necessary for good control,
handling, dealing with gusts etc.

I think you did miss one slight concept however, that when we are on
tow, our attitude is slightly more nose up at a given speed, than what
the nose attidude would be at the same speed while not on
tow.......thrust is the variable ....

Most gliders tow with a slight nose up attitude....So if you release
from tow, and maintain the same nose attitude, or even raise the nose
further as you suggest, I think you will find a rapid decrease in
airspeed...not to mention that the thought of raising the nose while
turning, while low, just sends shivers down my spine.....

On a rope break, I instruct my students to establish the same nose
down attitude that would be used in a "normal" pattern. I find that
making the turn seems to work out well for most pilots, but the
decision making after the completion of the 180 is often
lacking......they do not recognize the problems associated with a down
wind landing...(use of spoiler and need for slip for instance)

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