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View Full Version : Horton STOL 172 "V" speeds


R. Wubben
December 29th 03, 02:08 PM
I've just bought a '62 Cessna 172 with the Horton STOL kit and madras
droop tips and have a question:
My dad took it up for the first time (it's in WI, I'm in NC) and was
curious about if these modifications change the "V" speeds in any
significant way...? Apparantly there is no change in the POH after
these modifications, but obviously there must be some difference.
Specifically how Vx and Vy would be different, best glide, and what to
approach at. He and the instructor were using 75-80 as the approach
speed (which seemed high to me). Does the sink rate increase noticably
with these modifications?

Thanks for any insight!
Ryan Wubben
Chapel Hill, NC

C J Campbell
December 29th 03, 03:05 PM
Any change in V speeds should be noted in the supplemental type certificate
that comes with the mod. The STC should also describe any other changes in
flight characteristics.

Dale
December 29th 03, 05:40 PM
In article >,
(R. Wubben) wrote:

> I've just bought a '62 Cessna 172 with the Horton STOL kit and madras
> droop tips and have a question:
> My dad took it up for the first time (it's in WI, I'm in NC) and was
> curious about if these modifications change the "V" speeds in any
> significant way...? Apparantly there is no change in the POH after
> these modifications, but obviously there must be some difference.
> Specifically how Vx and Vy would be different, best glide, and what to
> approach at. He and the instructor were using 75-80 as the approach
> speed (which seemed high to me). Does the sink rate increase noticably
> with these modifications?

I fly 206s that have a Sportsman STOL kit (leading edge), VGs and the
WingX STOL wingtip extensions. There is a significant improvement in
the performance of the airplane with these mods, yet the only speed
change was a reduction in Vne with the WingX extensions.

As I understand the companies in their adds will make claims of
performance gains, but make no "official" claim of a change in a/c
performance negating a lot of expensive testing to get approval. Make
no claim and you don't have to prove anything.

--
Dale L. Falk

There is nothing - absolutely nothing - half so much worth doing
as simply messing around with airplanes.

http://home.gci.net/~sncdfalk/flying.html

JFLEISC
December 29th 03, 10:40 PM
>I've just bought a '62 Cessna 172 with the Horton STOL kit and madras
>droop tips and have a question:
>My dad took it up for the first time (it's in WI, I'm in NC) and was
>curious about if these modifications change the "V" speeds in any
>significant way...? Apparantly there is no change in the POH after
>these modifications, but obviously there must be some difference.
>Specifically how Vx and Vy would be different, best glide, and what to
>approach at. He and the instructor were using 75-80 as the approach
>speed (which seemed high to me). Does the sink rate increase noticably
>with these modifications?

My wife's 172B has the Madras tips and the STC does specify a placard noting a
lower Vne and Va (I can't recall the exact numbers at the moment) but I'm
pretty sure there is no notation on Vx or Vy.
With two people in front and full fuel it just won't stall (just mushes out
with "0" indicated air speed) but I think that is due to running out of
elevator more than the mods. I don't think it takes off any better than any
other 172 but I notice it "floats" alot on landing. Her instructors seem to
think it 'likes to fly' better than other 172s they teach in and it seems
unusually fast but I bet it's just rigged correctly more than anything else.

Jim

Rick Durden
December 29th 03, 11:47 PM
Ryan,

There is no POH for your airplane.

The Owner's Manual has V speeds.

However, you MUST have the STC paperwork for the airplane for it to be
legal to fly. Look at the STC paperwork for any information on
speeds.

All the best,
Rick

(R. Wubben) wrote in message >...
> I've just bought a '62 Cessna 172 with the Horton STOL kit and madras
> droop tips and have a question:
> My dad took it up for the first time (it's in WI, I'm in NC) and was
> curious about if these modifications change the "V" speeds in any
> significant way...? Apparantly there is no change in the POH after
> these modifications, but obviously there must be some difference.
> Specifically how Vx and Vy would be different, best glide, and what to
> approach at. He and the instructor were using 75-80 as the approach
> speed (which seemed high to me). Does the sink rate increase noticably
> with these modifications?
>
> Thanks for any insight!
> Ryan Wubben
> Chapel Hill, NC

Hankal
December 30th 03, 01:00 AM
> Have him make sure that the stall warning horn is going off
>at touchdown and he will be amazed at how slow he'll be flying

I have the Horton and the 180 HP engine.
I float for ever if I try landing with more than
60 knots. My sink rate is higher than the average 172. I can land at 25 knots
nice and easy.
Very hard to stall.
Hank

R. Wubben
December 30th 03, 02:04 AM
That was my understanding...
My dad and the instructor went thru the paperwork and the POH and
found no mention of any change in the speeds. The instructor has
experience in a 180 hp 172 with the Horton kit and remembered that
they purposely did not change the "V" speeds.
But from a practical stand point, do they change...?

Thanks,
Ryan Wubben
Chapel Hill, NC

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