Duo Turbo Climb / Altitude performance

Look at the climb rate/altitude in the graph and time
to climb graph in the Duo T manual? These graphs are
realistic - for example I know that the Discus 2cT
graphs were derived from 11 hours of engine climb testing
time. The Duo T will only be expected to get as much
as 150fpm at low density altitudes.

BTW the advantageous climb rate of a self sustainer
isn't just the rate of climb above level flight but
the rate of climb above the rate of sink at around
max LD - so the Duo T at typical UK flying altitudes
is gaining almost 300fpm over its non turbo twin =
notionally 3000 feet higher after 10 minutes engine
burn and, crucially, about 10 miles closer to an airfield/ridge/th
ermal.

Even with zero rate of climb in the US midwest then
if the Duo T engine is started at a safe altitude then
the likelyhood of an off-airfield landing will be considerably
reduced - it just might not be the home airfield:-)





At 03:06 26 November 2005, Gary Emerson wrote:
Just to clarify just a tad, we shut down the turbo
at 6500 ft because we
had final glide back to home, not because we weren't
climbing. We still
had about 125-150 FPM up at that point. I've never
had a need to fire
it up at any higher altitude and so I'm curious if
anyone else has...
I'd love to hear that you could hold altitude at 10k
ft.

BTIZ wrote:
ok... I have received two lashes with the noodle that
the Duo T is a
'sustainer' and not self launch...

but by the same token... of the Duo T can only 'sustain'
6500MSL DA... it is
nothing more than a glider out here... I'll admit...
I did use that word
'take off' in regards to 'sustainer' operations

The POINT is that Density Altitude during standard
summer operations will
make the use of the 'sustainer engine' worthless.
6500DA is below GROUND
LEVEL in our peak flying season, maybe it will only
extend the glide back to
something landable.. but I would not want to count
on it to 'maintain
altitude'.

But then again.. with temps such as these.. we don't
need no stinking
engine.

BT

'BTIZ' wrote in message
news:swNhf.4913$pF.4792@fed1read04...

Now that is an interesting data point... I'd be interested
in others
also..

If that DuoT can't climb above 6500ft MSL at better
than 150fpm, then I
would not even attempt a takeoff out here in the summer
time. Airport
Elev, 2833MSL, Baro 30.00, Temp 100F, puts the DA at
6000ft. Granted there
can be found a thermal right on the runway to assist,
but there is also
strong down near strong up.

Another favorite launch site, at 5500MSL, Baro 30.00
and 90F puts the DA
at 8500, even if the temp is still only 80F, the DA
is 7940.

I've noticed a DG500M on the market that flies regularly
out of Colorado,
would the seller care to offer some data points?

Maybe the DG808B?

BT
'Gary Emerson' wrote in message
news
Greetings,

Looking for some real world data on what the max altitude
that a Duo T
can sustain level flight. Would also be nice to know
what sort of climb
performance people have seen at lower altitudes. I
know it'll climb to
6500ft MSL and average around 150 FPM, but hoping to
get more data
points.

Gary

John Galloway wrote:
Look at the climb rate/altitude in the graph and time
to climb graph in the Duo T manual? These graphs are
realistic - for example I know that the Discus 2cT
graphs were derived from 11 hours of engine climb testing
time. The Duo T will only be expected to get as much
as 150fpm at low density altitudes.


Do you have a D2CT? What does its manual show as its climb rate at a
density altitude of 6,000' and 10,000' (just marginally above the Nevada
terrain on a hot day)?

John Galloway wrote:

Even with zero rate of climb in the US midwest then
if the Duo T engine is started at a safe altitude then
the likelyhood of an off-airfield landing will be considerably
reduced - it just might not be the home airfield:-)

With my self-launcher, I usually (but not always) consider 1000' agl a
safe altitude to start the engine . In the situation you describe, what
would you consider a "safe altitude"? High enough to fly level to the
airport, or would you count on some climb along way, or ?

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA