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Dave Russell
April 3rd 04, 04:03 AM
My latest endeavor has been to learn to snap-roll the Super D. A
couple of training flights in an Extra 300 proved that I could learn
to fly them, but transferring that experience to the Decathlon has
been humbling. (As an aside, I *strongly* suggest you do not go fly
an Extra 300 when you own a Decathlon. I *love* the Super D and all,
but Holy Cow, Batman! The Extra is simply an astonishing machine.)

Anyway, my snap rolls suck. The break is mushy, the rotation is
sloppy, my exits are horrible. The rotation is slow enough that I
actually can 'think' while it goes around, but I haven't been able to
get any meaningful acceleration with forward stick.

Any Decathlon instructors wanna gimme a few tips? (And *please* don't
tell me to just trade up to an Extra... poking fun at an addict in
withdrawl is cruel and mean.)

Dave Russell

jsmith
April 3rd 04, 04:14 PM
Dave, one of the reasons we stopped doing snaps in the lower competition
levels was because of seats breaking in the Decathlons and Citabrias. As
with many maneuvers, people are flying their entries too fast, causing
higher forces on the airframes and components, causing things to break.
(Remember the Pitts longeron breaks? Pitts put out a really good report
based on the testing they did to determine why their airplanes were
breaking this way.)
Eric Mueller's book recommends practicing your maneuvers at the slowest
possible airspeed which will allow completion without stalling.
This serves to provide control feedback to the pilot and reduce the
forces on the aircraft.

Dave Russell wrote:
> My latest endeavor has been to learn to snap-roll the Super D. A
> couple of training flights in an Extra 300 proved that I could learn
> to fly them, but transferring that experience to the Decathlon has
> been humbling. (As an aside, I *strongly* suggest you do not go fly
> an Extra 300 when you own a Decathlon. I *love* the Super D and all,
> but Holy Cow, Batman! The Extra is simply an astonishing machine.)
> Anyway, my snap rolls suck. The break is mushy, the rotation is
> sloppy, my exits are horrible. The rotation is slow enough that I
> actually can 'think' while it goes around, but I haven't been able to
> get any meaningful acceleration with forward stick.
> Any Decathlon instructors wanna gimme a few tips? (And *please* don't
> tell me to just trade up to an Extra... poking fun at an addict in
> withdrawl is cruel and mean.)
> Dave Russell

Rich Stowell
April 5th 04, 03:40 AM
(Dave Russell) wrote in message >...
> My latest endeavor has been to learn to snap-roll the Super D. A
> couple of training flights in an Extra 300 proved that I could learn
> to fly them, but transferring that experience to the Decathlon has
> been humbling. (As an aside, I *strongly* suggest you do not go fly
> an Extra 300 when you own a Decathlon. I *love* the Super D and all,
> but Holy Cow, Batman! The Extra is simply an astonishing machine.)
>
> Anyway, my snap rolls suck. The break is mushy, the rotation is
> sloppy, my exits are horrible. The rotation is slow enough that I
> actually can 'think' while it goes around, but I haven't been able to
> get any meaningful acceleration with forward stick.
>
> Any Decathlon instructors wanna gimme a few tips? (And *please* don't
> tell me to just trade up to an Extra... poking fun at an addict in
> withdrawl is cruel and mean.)
>
> Dave Russell


Hi Dave,

It's probably way easier for me to show you how to do them than to try
to explain them here. In the end, it has to do with timing. That and
the fact that you need not (better not) bury the elevator control full
aft.

Here's what I suggest you try in your airplane:

Establish level slow flight at 85 mph. Leave the power alone
thereafter. Mentally give yourself a countdown -- 3, 2, 1 -- at 1,
smoothly but briskly apply full rudder as you would for any spin
entry. When you sense that the rudder is passing though 3/4 of its
full travel, "flick" the elevator aft just far enough to induce the
stall. At 85 mph, that'll be about a 2 to 2-1/2 G tug on the stick.
You want to generate that G with as little stick movement as possible.

As soon as the airplane snaps, release a touch of the aft elevator.
Wait until nearly upright, then apply full opposite rudder followed by
rudder neutral. In the Decathlon, you will also likely need full
opposite aileron to keep that long, thick wing from over rotating
during recovery. The elevator doesn't really need to move at all
during recovery if done properly.

Also, the Europeans use better terminology for the maneuver, calling
it a "Flick Roll" -- which really is pretty close to how you should
move the elevator. I liken the elevator movement to casting a fishing
line: flick your wrist rather than yanking the pole with your entire
arm/shoulder.

Again, I could show you in less than 30 minutes, but you insist on
going to AZ to fly those darned Extras ; )

Rich
http://www.richstowell.com

Borislav Deianov
April 5th 04, 11:32 PM
Rich,

Rich Stowell > wrote:
> (Dave Russell) wrote in message >...
> > Anyway, my snap rolls suck. The break is mushy, the rotation is
> > sloppy, my exits are horrible. The rotation is slow enough that I
> > actually can 'think' while it goes around, but I haven't been able to
> > get any meaningful acceleration with forward stick.

I have the same problem as Dave, except I'm flying a Citabria 7KCAB
(fixed pitch, 150hp). And it's only a problem when I fly solo. I can
do a reasonable snap roll with an instructor in the back.

> Here's what I suggest you try in your airplane [Super D]:
>
> Establish level slow flight at 85 mph. Leave the power alone
> thereafter. Mentally give yourself a countdown -- 3, 2, 1 -- at 1,
> smoothly but briskly apply full rudder as you would for any spin
> entry. When you sense that the rudder is passing though 3/4 of its
> full travel, "flick" the elevator aft just far enough to induce the
> stall. At 85 mph, that'll be about a 2 to 2-1/2 G tug on the stick.
> You want to generate that G with as little stick movement as possible.

Here are the steps I was taught for the 7KCAB:

- 1800 RPM, slow to 65mph
- 2200 RPM and lower the nose to accelerate to 80mph
- flick the elevator and as the nose goes through the horizon, briskly
feed in the rudder
- recover with opposite rudder and slight forward stick
- recovery seems to take about 1/2 turn rolling left, 1/3 turn rolling right

This works pretty well when flying dual but I'm always getting mushy
slooowww rolls when trying it solo (if I'm able to make it go around
at all). Any hints?

Thanks,
Boris

EDR
April 6th 04, 05:06 PM
In article >, Borislav
Deianov > wrote:

> I have the same problem as Dave, except I'm flying a Citabria 7KCAB
> (fixed pitch, 150hp). And it's only a problem when I fly solo. I can
> do a reasonable snap roll with an instructor in the back.

Fly solo from the rear seat.
It snaps reallly well!
Run some CG calculations for different fuel loads.

Dave Russell
April 7th 04, 03:10 AM
EDR > wrote in message >...

> Fly solo from the rear seat.
> It snaps reallly well!
> Run some CG calculations for different fuel loads.

May be illegal, but... my 7GCAA was well within the CG limits in that
configuration. :-)

-DJR

john smith
April 7th 04, 04:20 AM
Dave Russell wrote:
> EDR > wrote in message >...
>
>
>>Fly solo from the rear seat.
>>It snaps reallly well!
>>Run some CG calculations for different fuel loads.
>
>
> May be illegal, but... my 7GCAA was well within the CG limits in that
> configuration. :-)

Where does it say it is illegal?

Ditch
April 7th 04, 08:36 AM
>Where does it say it is illegal?

Isn't there a placard that says "Solo from front seat only"?


-John
*You are nothing until you have flown a Douglas, Lockheed, Grumman or North
American*

EDR
April 8th 04, 09:58 PM
In article >, Ditch
> wrote:

> >Where does it say it is illegal?
>
> Isn't there a placard that says "Solo from front seat only"?

What year?
There might be on the newer ones.

Rich Stowell
April 9th 04, 02:05 AM
Borislav Deianov > wrote in message >...
> Rich,
>
> Rich Stowell > wrote:
> > (Dave Russell) wrote in message >...
> > > Anyway, my snap rolls suck. The break is mushy, the rotation is
> > > sloppy, my exits are horrible. The rotation is slow enough that I
> > > actually can 'think' while it goes around, but I haven't been able to
> > > get any meaningful acceleration with forward stick.
>
> I have the same problem as Dave, except I'm flying a Citabria 7KCAB
> (fixed pitch, 150hp). And it's only a problem when I fly solo. I can
> do a reasonable snap roll with an instructor in the back.
>
> > Here's what I suggest you try in your airplane [Super D]:
> >
> > Establish level slow flight at 85 mph. Leave the power alone
> > thereafter. Mentally give yourself a countdown -- 3, 2, 1 -- at 1,
> > smoothly but briskly apply full rudder as you would for any spin
> > entry. When you sense that the rudder is passing though 3/4 of its
> > full travel, "flick" the elevator aft just far enough to induce the
> > stall. At 85 mph, that'll be about a 2 to 2-1/2 G tug on the stick.
> > You want to generate that G with as little stick movement as possible.
>
> Here are the steps I was taught for the 7KCAB:
>
> - 1800 RPM, slow to 65mph
> - 2200 RPM and lower the nose to accelerate to 80mph
> - flick the elevator and as the nose goes through the horizon, briskly
> feed in the rudder
> - recover with opposite rudder and slight forward stick
> - recovery seems to take about 1/2 turn rolling left, 1/3 turn rolling right
>
> This works pretty well when flying dual but I'm always getting mushy
> slooowww rolls when trying it solo (if I'm able to make it go around
> at all). Any hints?
>
> Thanks,
> Boris


Hi Boris,

Of course, someone in the back seat shifts the c.g. a bit more aft,
allowing you to attain slightly higher angles of attack and better
stall/spin departures.

I would recommend trying essentially the same thing I suggested to
Dave for your solo ventures, namely:

In your Citabria, establish level slow flight at 80 mph. Leave the
power as is for now (later you can try adding a bit more power, but
for now, work on the rudder/elevator timing).

Lead the snap roll with brisk rudder application followed by
sufficient aft elevator to stall (about a 2 G or so tug on the stick).
As soon as the airplane departs, release a touch of the aft elevator,
etc.

I believe rudder-then-elevator will have better results for you than
the other way around.

Let me know how that goes and we can continue with the lesson!

Rich
http://www.richstowell.com

Borislav Deianov
April 14th 04, 10:10 AM
EDR > wrote:
> In article >, Borislav
> Deianov > wrote:
>
> > I have the same problem as Dave, except I'm flying a Citabria 7KCAB
> > (fixed pitch, 150hp). And it's only a problem when I fly solo. I can
> > do a reasonable snap roll with an instructor in the back.
>
> Fly solo from the rear seat.
> It snaps reallly well!

The manual I have is for 7ECA, 7GCAA, 7KCAB, 7GCBC, effective serial
numbers -75 and up. It lists the following placard on the instrument
panel: "Occupy Front Seat When Flying Solo".

> Run some CG calculations for different fuel loads.

Good idea. Here are the results in several configurations (for the
airplane I fly):

dual, 1/2 fuel 15.59" c.g.
solo, full fuel 12.70" c.g.
solo, 1/2 fuel 11.90" c.g.
solo, empty fuel 10.98" c.g.

7KCAB aerobatic c.g. range: 10.6" - 16.0"

So more fuel will help when flying solo. Unfortunately, I don't have
too much flexibility there, as the FBO likes to keep about 1/2 fuel in
it (to stay under gross on dual flights).

Thanks,
Boris

Borislav Deianov
April 14th 04, 10:38 AM
Rich Stowell > wrote:
> Borislav Deianov > wrote in message >...
> >
> > I have the same problem as Dave, except I'm flying a Citabria 7KCAB
> > (fixed pitch, 150hp). And it's only a problem when I fly solo. I can
> > do a reasonable snap roll with an instructor in the back.
[snip]
>
> In your Citabria, establish level slow flight at 80 mph. Leave the
> power as is for now (later you can try adding a bit more power, but
> for now, work on the rudder/elevator timing).
>
> Lead the snap roll with brisk rudder application followed by
> sufficient aft elevator to stall (about a 2 G or so tug on the stick).
> As soon as the airplane departs, release a touch of the aft elevator,
> etc.

I tried this during my last session and I'm happy to report that it
worked very well! I was able to reliably snap it in both directions.
The roll rate was decent and accelerated a bit after releasing some
elevator input. Wow. I needed 1800 RPM to fly level at 80 mph.

The problem now is that the recovery after one turn leaves me in a
marked nose-down attitude. After a quick pull up to level flight, I
end up at about the same airspeed but 200' or so lower than the
starting altitude. Is there a way around that? More power and an
starting the maneuver more nose up, perhaps?

Thanks for you help!

Boris

Rich Stowell
April 14th 04, 06:14 PM
Borislav Deianov > wrote in message >...
> Rich Stowell > wrote:
> > Borislav Deianov > wrote in message >...
> > >
> > > I have the same problem as Dave, except I'm flying a Citabria 7KCAB
> > > (fixed pitch, 150hp). And it's only a problem when I fly solo. I can
> > > do a reasonable snap roll with an instructor in the back.
> [snip]
> >
> > In your Citabria, establish level slow flight at 80 mph. Leave the
> > power as is for now (later you can try adding a bit more power, but
> > for now, work on the rudder/elevator timing).
> >
> > Lead the snap roll with brisk rudder application followed by
> > sufficient aft elevator to stall (about a 2 G or so tug on the stick).
> > As soon as the airplane departs, release a touch of the aft elevator,
> > etc.
>
> I tried this during my last session and I'm happy to report that it
> worked very well! I was able to reliably snap it in both directions.
> The roll rate was decent and accelerated a bit after releasing some
> elevator input. Wow. I needed 1800 RPM to fly level at 80 mph.
>
> The problem now is that the recovery after one turn leaves me in a
> marked nose-down attitude. After a quick pull up to level flight, I
> end up at about the same airspeed but 200' or so lower than the
> starting altitude. Is there a way around that? More power and an
> starting the maneuver more nose up, perhaps?
>
> Thanks for you help!
>
> Boris


Glad to read things are coming along, Boris! Now for your next
practice exercises:

Exercise 1 -- Establish level slow flight at 80 mph and 1800 rpm.
Increase power to 2000 rpm and initiate a shallow, stablized climb at
80 mph. Perform snap rolls exactly as described earlier, using the
rudder-elevator sequencing.

Practice the same from a climb at 80 mph and 2200 rpm; then again
climbing at 80 mph and 2400 rpm.

Exercise 2 -- Establish level slow flight at 70 mph (probably still
close to 1800 rpm). Leaving the power alone, lower the nose *a little*
and allow the airplane to accelerate. Perform the snap roll as the
needle hits 80 mph.

Practice the same from 70 mph and 2000 rpm, 70 and 2200 rpm, 70 and
2400 rpm. In each case, lower the nose toward the horizon and snap at
80 mph. The idea is to sneak up on 80 mph from 70 mph, so don't stuff
the nose down when trying to accelerate form 70 to 80. Lower the nose
"just enough" to accelerate to 80.

These exercises are designed to steadily and incrementally increase
the rate of snap while still working on the timing of rudder and
elevator actions, all the while not exceeding 80 mph.

Also during the recovery, try not to move the elevator forward at all
-- just full opposite rudder and perhaps full opposite aileron if
needed to prevent over-rotating. You've released a little of the aft
elevator once the snap begins, and this may be all the forward you'll
need from that point on.

Report back...

Rich
http://www.richstowell.com

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