At 04:31 PM 4/11/2008, you wrote:
Fact: there is change and new development happening. Yes, it is wise
to be cautious - but don't be so negative!
I'm not being negative. I worry when magical thinking is
substituted for rational analysis.
Fact: Ultralights / Microlights / Recreational planes are being
developed and utilised for glider towing (already overseas, OZ will follow).
Yes I've been saying this for years, including that the 120HP Jabiru
is worth investigating. However gliding has just gone for 18 metre
gliders with 600Kg gross weights which in this country need to be
launched at relatively high density altitudes. This might take
towplanes with lots of excess power to work properly.
One of the reasons that glider launching is potentially hazardous is
that more than one person is involved and all but one aren't flying
the glider and the communications between them is a long way from good.
Now what's going to happen if a turbo is launched behind a low power
tug and the turbo stops at low altitude? This will be like opening
the divebrakes on a normal glider. We've introduced another failure
mode. Let's stop and think about this and the failure modes before
blithely putting this in widespread use.
Fact: development doesn't stop - someone might even design a
<goog_1225776197087.htm>"Carbon Pawnee"
style<http://www.cubcrafters.com/news_item.aspx?id=100> aeroplane,
engine power will increase. (The Jet design for gliders is doing
nicely: just have a look at the 304S Jet)
The 304 jet is a self retrieve only. 90% of the hassle and 10% the
utility of self launch. Anyone got a number on the price of the installation?
I'm well aware of jet development having just designed the spark
ignition and extend/retract controller and engine data readouts for
our jet engine. I'm also aware of the PIK27 and have seen the
fuselage frames at Bob Ward's place. It uses a Rotax 914 turbo and I
have it from someone who maintained a couple of aircraft using them
for years that the best he got out of an engine was 700 hours before
things started breaking and falling off the engines. This doesn't
apply to the 80Hp or 100 HP 912 apparently. The 914 turbo probably
isn't that much cheaper than a 160 Hp Lycoming which properly cooled
with means to keep the engine warm in descent (assuming a dedicated
towing installation) would make the launch quicker and safer with the
same size airframe.
I've also seen that somebody in the US is using a microturbine as a
gas generator for a turboprop. I'm not a believer in this as by the
time you organise a power turbine, prop drive, maybe a reduction gear
and propeller you may as well use a second jet in a glider and avoid
the drag problems of propeller extension, housing while retracted
etc. While the propulsive efficiency of a turbojet in a glider isn't
good(it is around 10 -11%) this is about the same as the effective
propulsive efficiency of a launch behind a Pawnee but you aren't
flying the Pawnee in the jet case so you actually should save on fuel.
Fact: GFA member numbers are decreasing. Same for ACTIVE and regular
PPL pilot numbers.
Yep. But is there a tug pilot shortage? BTW I have it on good
authority that in the UK a PPL comes with a glider towing ability. No
training, they just assume anyone who can fly and is properly briefed
can fly a launch of a glider. I've experienced similar in the US with
no problems.
Fact: RA-Aus membership numbers are still increasing.
yep
Fact: Safety in RA-Aus is improving.
Dear God I hope so. Is there some reason RAAus flying should be so
much more dangerous than crop dusting per hour? Do you have any
statistics to back this assertion that it is getting safer?
Fact: CASA is still in denial and does still not fully recognise the
ICAO system. (at least they are taking steps to get there)
?????? There's nothing ICAO compliant about LSA or RAAus or any pilot
qualification short of a PPL.
Fact: the stuff we breathe and fly in is the same around the world.
(if not better in quality here in Australia)
Fact: I'd trust a good AME more than a bad LAME. (that missing "L"
does save monay!)
Fact: why do aircrafts need to be fixed once they come back to the
gliding club after being serviced / checked by a "LAME Organisation"?
I know of one carbon glider that was in for refinishing. It was found
that the leading edge(back to the spar) had been glued on with
microballoon mixture and was showing some signs of letting go. This
was a structural part. I picked up a new glider once to find a pocket
knife in the control mixer under the seat.
LAMEs don't have monopoly on making mistakes. I also had a LAME
appalled at the state of a tug that had been worked on by a gliding
club. If you are having trouble with your LAME get another one and
get close to him so that you know what is going on.
You still haven't identified any cost saving except a few LAME hours.
There's a cost increase for the pilots if they join the RAAus. I've
seen a gliding club where the tugs were maintained by the club
members who owned them, under LAME supervision. There wasn't a whole
lot of availability. That became quite an amusing story.
Mike
Borgelt Instruments - manufacturers of quality soaring instruments
phone Int'l + 61 746 355784
fax Int'l + 61 746 358796
cellphone Int'l + 61 428 355784
Int'l + 61 429 355784
email: [EMAIL PROTECTED]
website: www.borgeltinstruments.com
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