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Old April 20th 12, 03:59 AM
Ventus_a Ventus_a is offline
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First recorded activity by AviationBanter: May 2010
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Quote:
Originally Posted by Bob Gibbons[_2_] View Post
On Tue, 17 Apr 2012 12:46:24 +0000, Jim Pengelly
wrote:

Hi everyone,

I fly a Discus bT at the moment and absolutely love it. However, I
am thinking of upgrading to a flapped turbo in the next one or two
seasons and the Ventus bT/cT would seem to be the natural
choice.

I have heard conflicting opinions about the various models:

i) The bT has handling issues and the cT was designed to
overcome these issues, with a bigger rudder and some other
changes. The cT is the model to go for.

ii) The cT has handling issues, can be difficult to bleed approach
energy due to the brake configuration and was not a popular
model, which is why there are so few of them around. The bT is
the model to go for.

iii) The bT and cT perform relatively poorly in 15m mode rather
than their 16.6m (bT) and 17.6m (cT) modes, so competing in
15m mode is not recommended.

Any thoughts much appreciated.

Cheers,
Jim


I'll offer a few comments. My Ventus cT is a 1987 model and I've got
about 1500 hrs on the ship over the past 13 years.

-- One possible reason for the apparently small number of C models in
the US is that at least the early C's were brought into the US as B
models, and then re-placarded as a C model. My '87 cT has the original
B placard still in place, but X'd out with the new C placard mounted
below it. I notice that a number of Ventus B models in the FAA
database are in fact C models whose owners never updated the FAA
records.

-- I've got no complaints regarding the handling of the Ventus C,
thought I fly almost exclusively with the 17.6m tips. I've noticed no
issues with handling with the 15m winglets, however.

-- Unfortunately I have never had to opportunity to fly a Ventus B.
The only unbiased comment I can quote is from Derek Piggott in the Dec
1992 / Jan 1993 Sailplane & Gliding issue.

"Whereas the earlier model has rather a reputation for stalling and
spinning if flown carelessly. the C model seemed a model of docility.
I frequently pulled into steep thermalling turns, getting down to well
below 40kt with only an obvious buffeting and sinking feeling clearly
indicating that this was far too slow. It did not once drop a wing
requiring any proper stall recovery. In spite of the extra wing span,
the rate of roll is excellent at all speeds and it is easy to fly
accurately rolling into and out of turns"

-- Max gross with or without the engine is 500kg. The issue with the
engine in place is the 255kg non-lifting limit. With the engine in
place, the pilot weight determines whether the max gross of 500kg or
the non-lifting limit of 255kg kicks in first. For my weight and 28
gal of water, I hit max gross just before I hit the non-lifting limit.
Bottom line, with the engine in place and ballasted to max gross, you
are at the same loading as without the engine, but you cannot dump
down to the same low loading as without the engine. With the engine
in, I can go from 10.1 lbs/ft2 max down to 7.9 lbs/ft2 min. Without
the engine, W/L ranges from the same 10.1 lbs/ft2 down to 7.2 lbs/ft2
(all with 17.6m span). The B model has the same issue and limitations.

-- For what its worth, only the C models were factory certified with
the 17.6m tips.

-- Regarding the air brakes, I have never found a situation where
landing flap and full dive brakes were inadaqute. That said, they
probably are not the equal of a PIK 20B or any other ship with full
90deg flaps (I've got about 2500 hrs in a 20B, before the Ventus).

Hope this helps your decision.

Bob

Every Ventus cT manual that I have looked at says the max weight with the engine in is 430 kg regardless of the span. With the engine out, 500kg at 16.6. and 17.6m respectively

Cheers
Colin
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Last edited by Ventus_a : April 20th 12 at 04:07 AM.