These pages are a collection of the ideas and impressions of the
Cardinal pilots who frequent this site. This information is anecdotal
and informal, and may not be completely accurate.
As always, the Cessna operations and flight manual, and the advice
of a certified flight instructor, should be your primary source of
information regarding the safe operation of your aircraft.
Contents:
What is the Cardinal Crowhop?
Causes
Fixing it
Long term prognosis
What is the Cardinal Crowhop?
The story is fairly consistent. The pilot has a few hundred hours
and has recently stepped up to complex. Most of the flight
time is in either a 152 or 172, and by this time the pilot
has become quite accomplished at crosswinds, short fields
and so on.
So the pilot approaches this short, gusty landing with
confidence. Usually they've made a few dozen Cardinal
landings with no problem. But sure enough, this time
a gust lifts the nose just as the mains are about
to touch. No problem, the pilot knows from years of Cessna
experience just how much elevator to push in to arrest
the impending balloon.
Suddenly the occupants are startled to feel the nosewheel
contact the runway. Not hard, just a little bump, but it
throws the airplane back into the air, this time with a
little more dramatic angle of attack. The pilot takes action,
again a familiar action in just-the-right amount.
The second impact is a little more dramatic, and the pilot
has one of two reactions: either power up and start this
over or gosh-darn-it I can wrassle this thing to earth!
Most such events end up with a successful landing, either
as airspeed decays or in a second landing attempt. But in
some cases the desire to land 'no matter what' will result
is a wrinkled firewall and a spranged nose strut.
Another way to start this cycle is by carrying a little
too much speed over the numbers. As you float down the runway,
bleeding off airspeed, you might worry that the end of the
runway is coming up fast. You might be tempted to 'plant it',
as you did so many times in the 152 you trained in.
The result is the same as above; a pushoff from the nose strut,
a pitchup, a reaction and a divergent cycle until everything stops
moving.
The Causes of the Crowhop
You could just say that a full flying stab is 'different' and
leave it at that, but with the Cardinal it's worth knowing how
it's different. There are three primary differences:
First, the stab has a lot more power. You cause a lot more
motivation toward movement of the nose when you move the
yoke in a 177 than in a 172.
Second, it is much quicker in response. When you change the angle
of attack on that stab your flight attitude changes right now. The
usual slight delay that you're used to in a 152 is not there.
Finally, the feedback force presented by the stab are very much
affected by the airspeed. It takes a solid push to move the
yoke at cruise speeds, while in the flare it takes almost no
force to move the stab through it's full range of travel.
I can't quote pounds pre G or other scientific data on this, but
I do know the feel is remarkably different from cruise to flare.
As one contribution to that effect note that the speed range between
cruise and flare is much greater than most other Cessnas.
To fully understand why it was built this way, you need to
go back to the beginning of the Cardinal.
The configuration of Cessna's new planned replacement for
the 172 was different: pilot seat forward, wing back. It has
been said that this was the reason for going to a full flying
stabilator. Another theory has it that this was a marketing
idea, not too different from the T tail that other manufacturers
tried out a few years later.
How to fix the Crowhop
Luckily the fix for this problem is easy, straightforward and
entirely mental. In fact flying a Cardinal in these situations
is far easier than most Cessnas.
My trick is this: When a gust of wind lifts the nose as you
cross the numbers, do nothing. Don't push the nose down, just
let it mush a bit and in moments you'll be back into the proper
attitude.
If the nose rises too high, or you see your airspeed decay
more than you are comfortable with,
add a little power. Again the nose will come right back down
and you can land normally.
Some people will add a lot of power, enough to stop the
descent, then pull power and try the descent again. There is
usually plenty of room to do this on a normal runway.. it may
add 500 feet to the landing roll.
And in a few situations you'll find it prudent to just power
up and take it around for another try.
Under no circumstances 'push the nose over' as you would in
a 152 or 172. That kind of overreaction is needed with those
aircraft's elevator response, but that's the motion that will
get you in trouble in a Cardinal.
If you're in the 'plant-it' situation, just remember not to
do that. Slip, slide or take it around again, but don't
expect putting the wheels down to make things better.
The Pilot's long term prognosis
So what is the reality for our fledgling Cardinal pilot?
Will this demon pop up from time to time or can it be
exorcised with good knowledge or training?
In my experience, no one ever does a crow hop more than a
time or two, if they understand the information above. The
situation is quite easily resolved once you realize what's
really going on.
In my case I had owned our Cardinal for 2 or 3 months when
I did my first one, at a flyin where people were walking
across the runway half way down it's 3000 foot length. All
the Taylorcraft and Cubs had stopped by that point, why not
a Cardinal? I tried to plant it and had quite a ride before
it came to a stop.
I did a lot of touch and goes, wondering what had happened,
and started to work out some of the dynamics of what was
happening (we engineers tend to fixate on things like that.)
But 3 months later a gusty crosswind and short runway caused
the same effect. This time I punched the power and settled
back in nicely.
I've ridden with other pilots who have done this, and on
one or two occasions my hands have risen, unbidden, to provide
help that in a rational moment I would never have offered. In
both cases the answer was to simply hold full back and let the
energy decay.
So in conclusion, don't be afraid of it, but do take the time
to understand how it works. Feel the forces required in cruise,
then slow to stall and compare. Check out the edges of your
Cardinal's performance, don't be afraid to make it do what
you want: it is more capable than any other Cessna of doing
what you ask.
You will be rewarded with controlled and safe landings from
that point on, with nary a hop to be concerned with.
Copyright Keith Peterson 1999
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