Why fly fast approaches?

EDR wrote
Prior to the flight I calculated a weight and balance and appropriate
speeds for the actual takeoff and landing weights.

This is required in large airplanes (Vref, anyone) and perfectly
reasonable in ANY airplane. All speeds change with weight. I think
what you did was fine. On the other hand, lots of people don't do it,
and simply use the full-gross speeds as published - and then maybe add
a few knots.

When we were on the ground, I asked him why he wanted the faster speeds.
His answer was that this was not a new airplane, so the book values
needed to be increased to allow for age related things that could
affect the noted V-speeds.

This is nonsense. If you have that much deformation of the wing, or
that much weight that is unaccounted for, the plane is not airworthy.

I can understand the reasoning for a student pilot

I can understand the reasoning for a student pilot too - but I don't
agree with it. Better to teach it right from the start.

I am thinking in terms of performance as would apply
to the Commercial standards. Hence, the reason for calculating the
necessary speeds prior to flight.

As I said - there's nothing wrong with your thinking.

I will add that flying at the instructor's recommended speeds leads to
float in the roundout and required more runway.

No kidding...

What is the perspective of the instructors in this group?

My perspective is that at 1200 hours, you might want to start thinking
about becoming an instructor yourself. What you experienced is,
unfortunately, more the rule than the exception, and is the kind of
nonsense that eventually prompted me to become an instructor.

Michael

On 1 Jul 2004 07:03:22 -0700, (Snowbird)
wrote:

(If you suspect a problem..)
WEIGH THE PLANE
and calculate a new, accurate empty weight.

There's also the point that if one stalls the plane and the stall
speed differs substantially from 'book' (or at less than gross weight,
calculated value), one can then adjust -- pretty close to your point
"fly the wing" except that I suggest exploring the envelope at altitude
first, in a new-to-the-pilot plane....

I completely agree.

z

"Snowbird" wrote in message
m...
I'll be interested in what others say, but my take on this is:

As far as I know, all the V-speeds you're talking about are a direct
function of stall speed.

For landing, true. For takeoff, not true. Vx and Vy, being the result of
excess thrust and excess power (respectively), depend not just on the fixed
characteristics of the airframe, but also the declining characteristics of
the engine (and are not directly related to stall speed in any case).

Now, that said, I agree with the others who point out that if the airplane's
performance has changed enough that the published V speeds are not correct,
then the airplane needs fixing. A slight reduction in engine power might be
expected, but one large enough that Vx and Vy have changed enough for the
pilot to notice warrants repair.

And as you say, even the airframe can suffer during its lifetime in ways
that might affect stall speed. But again, I'd say that if the stall speed
has increased above the published speeds, the correct course of action is to
fix the airplane.

And generally speaking, I wouldn't expect the stall speed to change in a way
noticeable to any but the most detail-oriented test pilot; changes in gross
weight are going to be much more significant, and those mostly occur due to
differences in loading (how many passengers, what weights, amount of fuel
carried, etc.). 30 pounds of accumulated junk, while not unheard of, is
still unusual, and even that much extra weight isn't going to produce a
noticeable change on the airspeed indicator when stalling the airplane.

I'm in complete agreement that it's foolish to add airspeed on landing. The
extra speed might put you farther away from some problems (premature stall)
but it's guaranteed to put to closer to other problems (long landing,
porpoising, nose strike, etc.). Adding airspeed to compensate for gusts is
reasonable, but adding airspeed just because you think the airplane is old
is not, and is unsafe.

Pete

C J Campbell opined

I think the instructor's reasoning is faulty. Why would the stall speed
increase as the airplane ages? If it has increased measurably, then
something needs to be repaired.

Bugs, dents, dirt would all change the shape of the wing. How much that would
change the stall speed is an open question. Perhaps the FAA could be useful
and do some research.

I don't even teach student pilots to fly faster than necessary. It is too
easy for a student to lose control on a fast approach, especially if he
balloons or bounces.





-ash
Cthulhu for President!
Why vote for a lesser evil?

"EDR" wrote in message
...
His answer was that this was not a new airplane, so the book values
needed to be increased to allow for age related things that could
affect the noted V-speeds.

Our airplanes are nearly sixty years old. Age hasn't affected their stalls
speed, but engine conversions, modifications, etc... do.

All the instructor has to do is go up and stall the airplane in various
configurations to get the actual numbers if he really thinks they are not
as published.

I fear the "more is better syndrome" has affected your CFI. A shame.

Deb

--
1946 Luscombe 8A (His)
1948 Luscombe 8E (Hers)
1954 Cessna 195B, restoring (Ours)
Jasper, Ga. (JZP)

On Thu, 01 Jul 2004 00:09:18 GMT, EDR wrote:

What is the perspective of the instructors in this group?
The instructor I fly with knows me. Why would he not hold me to
Commercial standards?

I'm not an instructor. But my perspective is that the person giving you
the checkout is just not doing it correctly.

Also, when you did your stall series as part of the checkout, it would be
pretty simple to verify the actual vs book stall speeds.

And when you did slow flight, it would be pretty simple to see how the a/c
behaves at 1.1-1.3 Vso.


Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

Nya - Nya! Mines a little heavier than yours. I am hauling around a 400
pound engine.
Michelle

G.R. Patterson III wrote:

Michelle P wrote:


Well then this instructor will be really un-comfortable in my airplane.
Final is done at 70-65 MPH (61-56 Knots).
Final landing is around 55 MPH (48 knots). ;-)



Nya - Nya! My Maule's slower than your Maule. My Maule's slower than yours! :-)

George Patterson
None of us is as dumb as all of us.



--

Michelle P ATP-ASEL, CP-AMEL, and AMT-A&P

"Elisabeth" a Maule M-7-235B (no two are alike)

Volunteer Pilot, Angel Flight Mid-Atlantic

Volunteer Builder, Habitat for Humanity

"Peter Duniho" wrote in message ...
"Snowbird" wrote in message
m...
I'll be interested in what others say, but my take on this is:

As far as I know, all the V-speeds you're talking about are a direct
function of stall speed.

For landing, true. For takeoff, not true. Vx and Vy

'Scuse, Peter, but I said "all the V speeds you're talking about",
not "all V-speeds".

As best I can tell, the original poster was talking about
Vr, and landing speed.

I don't think he discussed being asked to climb out at a different
speed than Vx or Vy, but in any event I think a better argument
can be made for that practice in appropriate circumstances.

Now, if you want to argue for Vr being a function of excess thrust
and excess power -- go ahead.

Cheers,
Sydney

On Fri, 02 Jul 2004 03:01:25 GMT, wrote:


On page 4-14 of the PIM (revised 6-18-84) in section 4.29, the following
text appears:

“The airplane should be trimmed for to an initial approach speed of 75 KIAS
with a final approach speed of 66 KIAS with flaps extended”

When I got checked out to fly the Cherokee Archer II ....

I'm not trying to throw stones, but I belive the Archer II has
slightly higher speeds referenced than the older models. The taper
wing has slightly different characteristics than the straight Hershey
bar wing.

z

"Snowbird" wrote in message
om...
'Scuse, Peter, but I said "all the V speeds you're talking about",
not "all V-speeds".

As best I can tell, the original poster was talking about
Vr, and landing speed.

Whatever. I find Vx and Vy to be perfectly relevant in this thread, even
looking at only the first post. You want to be offended, go right
ahead...wouldn't be the first time.