Auto engine in Pawnee tug (long)
P.Ir...@syd.dwt.csiro.au
P.Ir...@syd.dwt.csiro.au
over a number of years.
I have posted them before some time ago but there seems further
interest now.
Please note that I have NO connection with this project.
I just read the journal!
***************************************************************
Australian Gliding
March 1989
Progress Report- Car Engines for Tugs
by Dave Sharples
GFA president
The crippling costs of fitting a new en-
gine to a tow plane. whether it be Pawnee
or Cessna, has been the subject of much
debate over the past decade. Costs continue
to spiral ever moonwards. and in reality,
is the single biggest contributor to gliding
costs.
Addressing this problem with some
tenacity, Alan Seaman. back in July 1987.
suggested to the Gliding Federation of Aus-
tralia that the fitting of automotive engines
into light aircraft used for aero towing
gliders seemed to be a likely answer to the
cost spiral, and the problem that every club
has to eventually face.
There is ample evidence that the high
costs of periodic engine maintenance and
complete overhauls are driving clubs out of
existence.
The problem is not unique to gliding
either - the future of the American light
aircraft industry is just as bleak.
So. according to Alan, gliding should
therefore explore every alternative. In this
case, automotive engines ior tug aircraft.
Initial surveys of gliding clubs showed
that Lycoming 0-540 and similar motors
were costing as high as 9~?0.00 per hour
for engine maintenance alone. Spare parts
prices were seen to he verv high i.e. $700
for a new exhaust valve.
The proposal to pursue tug automotive
engines was canvassed amongst the gliding
movement. generating more response than
any proposal the GFA has put to the
members in recent years.
Javelin Ford 230 V6 motor conversion
Investigations started with the Ford
Windsor V6 installation which has virtu-
ally been on test (successfully) since 1980
by the Javelin Aircraft company in the
U.S.A. This motor appears to be a very ac-
ceptable replacement powerplant offering
a number of distinct advantages:
(1) Horsepower, without taxing rhe bas-
ic motor, in the 230-260 bracket.
(2) Low fuel consumption.
(3) Low vibration levels.
(4) Almost weight for weight against the
motors being replaced.
(5) Water cooled to reduce "thermal
shock" induced by the tugging mission,
hard climbs. followed by quick descents.
(6) The probability of maintenance be-
ing kept to gliding people with suitablc
skills.
(7) Major overhaul costs reduced to
perhaps 20% of the equivalent overhaul o(`
the original Pawnee or Callair aircraft
engine.
(8) Periodic maintenance costs also
reduced by comparison.
Weight specifications
With starter, alternator. carburettor, oil
filter, fuel pump, 6~ Ibs flywheel and
2 to I reduction drive, no oil, the Javelin
Ford Model 230 V6 engine of 3.8 litres
weighs 387 Ibs.
Reduction drive alone is 59 Ibs - a bare
engine 328 Ibs. This engine is 50 Ibs Lighter
than the Javelin Ford 140T (four cylinder
Mustang engine 2.3 litre), and is 90 cubic
inches more displacement.
Only 62 Ibs more than the 98T but 2.35
times the displacement, only 14 Ibs heavi-
er than the 0.360 Lycoming of 180 to 200
hp which weighs 373 Ibs, 101 Ibs lighter
than the 0-470 Continental which weighs
488 Ibs.
The weights given on air-cooled engines
are with exhaust system. carburetor air box
and baffles. (An air cooled engine can not
be operated without these components.)
With the 2 to I reduction drive. the swept
volume per propeller rotation is 464 cu
in. The compression ratio is 8.8 to I and.
due to liquid cooling, automotive fuel can
be used.
The cylinder heads and accessories covers
are aluminium. The thin wall steel block is
lighter than an aluminium block. The steel
block is 3/16 thick as compared to 5/8
thickness of an aluminium block.
This engine is known as a Windsor en-
gine. since it is manufactured in the Ford
Plant at Windsor, Ontario. Canada. The
production rate is 2500 per day and they
are used in many models of Ford cars and
trucks. Low mileage engines are available
from innumerable wrecks.
The following modifications are neces-
sary to convert the engine from an automo-
tive engine to an aircraft engine.
(1) Replace the valve lifters with non-
pump-up lifters.
(2) Replace the valve springs with
stronger springs.
(3) Replace the automobile camshaft with
an aircraft type camshaft.
(4) Delete the EGR system and open up
the intake method.
(5) Replace the stock carburettor with a
Holley 34-4412 with electronic leaning
(number 64 main jets).
(6) Modify the accessory pulleys to slow
down the alternator.
(7) Install the 2 to I reduction drive.
(8) Install the inboard engine mounts.
The Civil Aviation Authority
G.F.A. put a proposal to C.A.A. and
participated in a meeting with senior
C.A.A. engineers on 20 July 1988. This
resulted in an offer of total support for the
project and approval for a program to see
this project achieve finality.
(1) The prototype will be flown under the
Development category by way of ANO
101.31.
(2) On satisfactory completion of the de-
velopmental work "production" conver-
sions will be allowed to operate as "Spe-
cial Category" aircraft for glider tugging
work.
(3) There may be some initial operational
limitations which will eventually be
reduced, depending ultimately on reliabil-
ity and "safe history of operation".
This co-operative response from the
C.A.A. has been welcomed and is perhaps
indicative of the Authorities' concern about
the future of sport aviation.
Initial contact with the Ford Motor Com-
pany has also been very favourable with in-
dications that, where necessary, there will
be engineering and other assistance.
A business plan has been drawn up in-
volving a company structure and loan fund-
ing from a member from within the glid-
ing movement. The project is essentially a
private venture with limited involvement by
the Gliding Federation of Australia itself.
G.F.A. will however be offered a share-
holding (to be negotiated) and assist as ap-
propriate in C.A.A. and other negotiations.
It is the desire of the proponents that the
business be run as a successful, profitable
venture with any profits generated finding
their way back into the sport through
G.F.A.
The initial program to be followed has
been set down as:
(1) Procurement of a motor from the USA
, converted and ready to run
(The engine arrived in Melbourne in
January.)
(2) Procurement of Piper Pawnee fuselage
frame in which the first installation can
be made. engine test running complet-
ed and systems finalised ready for
transfer into an aircraft. (We have a
frame, courtesy of Drages Air
Museum.)
(3) Contracting with an operator to con-
vert a Piper Pawnee 235 which will al-
low a comprehensive test and develop-
ment program leading to "produc-
tion" conversions. First flight aimed
at March 1989. (The G.C.V. at Benalla
has made a 235 Pawnee available for
the program.)
How does it compare
Fig. I (below) compares prime features
of the Lycoming 0-540 motor removed
from the Piper Pawnee and the Javelin V6.
Participation
The project is a very significant one in
Australian aviation. but will only succeed
if it is supported by the people it is intend-
Figure 1. Comparison of the Lycoming 0-540 motor with the Javelin V6.
ITEM 0-540 230V6
Basic motor weight 398 Ibs 387 Ibs
Cubic displacement 541 cu in 464 cu in
Maximum horsepower 235 hp 260 hp
Propeller rpm 2575 2400
Fuel consumption (at 175 hp) 15.5 USg/h 10 USg/h
Compression ratio 8.5 : I 8.8 : I
Fuel type Avgas Mogas
ed for. It is an attempt by gliding people
to help gliding people.
Invitations have been extended to all in-
terested persons to register with "AUTO-
TUG" (care of the G.F.A. Secretariat)
which will allow them to be kept up to date
with progress. costing etc and ultimately
those who operate tugs to which this con-
version will apply will be able to indicate
their intentions towards it and the time scale
they have to meet.
Comments on the engine
The following comments have been made
by the chief engineer of Javelin, David
Blanton.
The public think that aircraft carburettors
will work at greater angles of pitch and roll.
but this has never been the case. Gravity
is always normal to an aircraft engine in
roll and only 10 deg. in pitch. in climb and
descent. Automobiles must endure 30 deg.
in pitch and roll. (Farm tractors are good
for 45 deg. in pitch and roll).
People assume the car motor is heavy.
We tell them its 100 Ibs lighter than an
0-470 Continental of the same power. It is
the same weight as a 180 hp Lycoming if
you have a constant speed metal prop on
the Lycoming and a fixed pitch Scimitar
prop on the V6.
We demonstrate 43% less fuel consump-
tion at the same E.G.T. as an air-cooled
engine. Continental engines are now com-
ing out with liquid-cooling and Lycoming
will be forced to follow suit.
We started out looking only for an eco-
nomical engine. We never dreamed of a
lighter engine or a smoother engine or a bet-
ter performing engine. We did not even
dream of 43% less fuel consumption. we
were just after an economical engine. But
now we have a fun engine, and this is what
makes us feel humble and we realise we
should count our blessings.
We have seven airplanes in the family
company including a new Mooney M-20.
Our kids leave them to sit on the ground
in preference to their enjoying flying the
V6.
It cost us $150,000 to learn that a tur-
bocharger doubles the fuel consumption.
You must hang radiators all over the air-
plane trying to cool it and the heat of the
exhaust system will incinerate fibreglass
cowling and firewalls.
When Ford started building the 230V6
in 1980, Ford engineers would say "that's
the one you should be flying". At the time
we had a romance going for the little
Escort engine with the turbo. We were at
Ford running the turbo Escort engine on
their dynamometer, and would walk
around the Windsor V6 and ignore it.
One day some of the Ford engineers
started one that was not even bolted down.
It was just sitting on the noor and they
would go from idle to 4800 rpm and back
to idle and it just sat there and never
moved. From that moment on we knew
that was the engine we should be flying. But
it took another two years to design a reduc-
tion drive for it and buy a test bed Cessna
175 and get it in the air.
Right from the first flight we knew we
had a winner. We now have nown the V6
for 600 hours with perfect success. We have
never touched a rod bearing or main bear-
ing. We have never failed a rod or head
gasket. We have never failed a valve. The
engine just operates perfectly.
The V6 will give years of service and if
you ever get enough time on it for it to need
an overhaul, this can be done for $300 to
$400. We have talked to a large number of
people who have been quoted
$10.000/$I2,000 to overhaul a certificated
engine. To most of us, this is an impossi-
ble cost to accept. How many people will
spend as much to overhaul an engine as
they pay for a home? (Note:- These are
U.S. costs in U.S. dollars.)
Nobody realises just how terrible the
beating and pounding there is on a direct
drive engine - until you fly our V6 with
the belt drive. We can't blame people for
thinking that they want a turbocharger be-
cause we used to think the same. We had
to fly turbo-charged motors for five years
and spend $150.000 before we concluded
they are just a gimmick to sell cars.
We can't blame people for having doubts
about the cog belt - we had them too at
first. It took several years experience be-
fore we knew they are indestructible.
We can out-climb just about every air-
plane in Wichita. We have given over 500
demonstration flights and on each flight we
show 2000 fpm rate of climb. We have been
to 10.000 feet many times and once to
18,000 ft. If anybody wants to question our
horse power just let them follow our old
Cessna 175 to 18,000 ft. You are only get-
ting 52.1% power at that altitude.
We use the same propeller that comes on
the G0-300 Continental but turn it faster
at full throttle. At cruise we turn the same
84 in diameter 67 in pitch prop on 50%
power that the Continental turned at 75%
power and we are only using 6.8 gph. The
Continental used 10 to 12 gph. We have the
light weight and the low fuel consumption
that we dreamed about years ago but we
never dreamed about such a good engine.
It's a fun engine.
The public does not realise how terrible
the beat and pound is on a direct drive air-
craft engine until they have flown behind
a converted automobile engine. Most
people who ny the Javelin Ford V6 get out
and say. never again do they want to fly
behind a beat and pound direct drive en-
gine. They also like the 6.8 gph in place of
ten to twelve gph, and the public like to
hear that they can overhaul the Javelin
Ford V6 for $400. US.
Fuel consumptiun
Due to the high price of fuel. low fuel
consumption is of paramount importance.
three years ago we advised the Voyager
crew that they should be using a liquid
cooled engine instead of a fuel cooled en-
gine to go around the World. AII air cooled
engines require an excessively rich mixture
to help cooling.
Continental motors agreed with this ad-
vice and developed the liquid cooled 0-200
engine for the rear of the Voyager. With
liquid cooling the fuel consumption for the
power setting they were using dropped from
4.8 gph to 2.8 gph. There is no possibility
the Voyager would have made it without
liquid cooling on that rear engine.
AII new Continental engines are coming
out with liquid cooling. Lycoming will be
forced into this also. It's only a question
of time. In most cases the engine manufac-
turer does not just take lower fuel con-
sumption into consideration. They increase
the compression ratio to get more power
and take about U of the increase in effi-
ciency in reduced fuel consumption.
AII reciprocating engines need to turn a
reasonable rpm to get their weight to pow-
er ratio down. The dynamics of reciprocat-
ing engines show that 5400 rpm is a good
compromise, and a large majority of
reciprocating engines are rated at this rpm.
Some a little less and some a little more.
Most little engines are rated at 7500 rpm.
Nearly all of the Ford V8s are rated at 5400
rpm. The 230 V6 is rated at 4800 rpm whilst
the Escort is rated at 6300 rpm.
Air cooled engines are not limited by dy-
namics but by cooling. Every time Con-
tinental and Lycoming have tried a reduc-
tion drive to the propeller. the engine would
give poor service due to over heating. Now
with the advent of liquid cooling we will
see more geared engines. We are proud that
Continental moIors had the good judg-
ment to switch over to liquid cooling. They
have put up with the foolishness of air cool-
ing for fifty years.
Radiator installations are not going to be
a problem due to the work we have done.
We can tell you how to do it today when
we could not have ten years ago.
We have seen gear drives fail. We have
seen planetary gears fail. We have seen
chain drives fail. We have seen V-belts fail.
We have never failed a cog belt. We have
never so much as damaged a tooth. We
know if you put on a narrow belt you can
fail it but if you provide for a wide belt like
we use, it's indestructible.
Dave Blanton is an obvious enthusiast,
but what do others think about his develop-
ments? From American aviation journals,
we print below several unsolicited
testimonials.
"l had a ride today in Dave Blanton's test
bed Cessna with the V6 and Dave's belt
drive. The ride and performance was every-
thing that Dave claimed. The first thing I
noticed was how quiet and how smooth. In
contrast to the air-cooled engine; no vibra-
tion at all. We also talked while taxiing and
in flight in near normal voice-sound levels.
"The performance that Dave has
described in his letters and manual are con-
servative. He pulled a chandelle at 75-80
IAS and the climb was just a notch over
2000 fpm with no loss of IAS at 2000
prop rpm (about 4000 engine rpm) that big
Cessna went to 140-145 IAS, without ef-
fort. I have done the right thing in dump~
ing my Lycoming 360-A and going with the
Javelin system."
Kenneth Mitchell Ph.D.
"An exciting flight to say the least. We
had 50 g of fuel aboard with two 200 Ibs
people. Climb was in excess of 2000 fpm.
Puts you back in the seat like a jet,
but we were in a Cessna - no noise no
vibration. In a word "FANTASTIC".
Bob Johnson
"The first flight of Javelin Ford was in
my 2 + 2 Sportsman. The pilot was so ex-
cited that he couldn't do much of anything
but check a few gauges. On subsequent
flights though I settled down and made
some basic performance checks; tail up and
off in less than 300 ft., hold air speed at
70 kts indicated and all I can see is sky. full
power straight and level 120 kts indicalecl.
"A medium climb out is as you would
in a normal airplane. The air speed just
goes through 80 - 90 - 100 kts indicated.
Vertical speed check pegged on 2000 fprn.
"To answer the question everyone has
been asking - does it have the power? Yes!
I would like to make a statement though
about the builder's manual. It seems like
a lot to read. There are some very subtle
points made. This is valuable information.
Stick to it."
Roy Rickman
In a letter to Mike Burns of the Gliding
Federation of Aust: 11ia, dated 28 Septem-
ber 1988. David Blanton wrote that he had
received their remittance for the engine.
$US5400.
Blanton went on to say that he bought
an engine out of a 1985 Ford Thunderbird
which had been in an accident, lost its left
front wheel, with the right side and rear
damaged beyond repair. The grill was not
broken so there was no chance of damage
to the engine. (Blanton pointed out that
there are at least 200,000 3.8 litre V6's lay-
ing around like this in the USA.)
"This particular motor" he wrote "has
throttle body fuel injection. and in hind-
sight I should have held off for a 1984
model motor. The engine has done 46.000
miles, which is low mileage, but the owner
never changed the oil. so the engine was
cruddy inside. They can be cruddy, but it
does not hurt the engine. Everything checks
out fine.
"We disassembled the engine last Thurs-
day, took the block and heads to be boiled
out. We shipped the camshaft to Detroit.
We have all the parts ordered from Ford,
new distributor. new carburettor, new
lifters and new springs. We will assemble
it with heavy duty Clevite bearings. I am
having the crankshaft polished. This is
recommended with hard bearings.
"We have had bad experience with the
Ford chrome rings. They are too severe and
don't sit in. We will use black iron rings.
Our company airplane takes a quart of oil
every 5 hours and with black iron rings. we
use a quart in 15 hours. We get more pow-
er out of the black iron rings.
"I am going to put in the spares that I
think you should have, like 2 sets of spark
plugs, 2 oil filters. case of 50W racing Val-
voline Oil, I set of bearings, I set of rings,
and I gasket set for the 1000 hour overhaul.
You could go to 2000 hours if you want.
The chrome rings will go 3,500 hours, the
black iron rings should be about gone at
2.500 hours.
"The box the motor will come in is a test
stand. You remove the screws and take off
the cover. Set in a battery and hook up the
fuel. Put in coolant and start it and run it.
You should have the oil pressure gauge and
temperature gauge that you are going to use
in the airplane connected up to the engine.
"The engine has a frequency where it will
shake at about 1500 rpm. but we don't
operate anywhere near that rpm. Turn it
up to 2000 rpm for about an hour. You can
put a fan on the radiator.
"Finally, I want you to have a party and
have all your club members standing
around when you open the box. It will be
blue-black and chrome and will look bet-
ter than any Lycoming or Continental you
have ever seen.
"Incidentally. we have decided you don't
need a spare drive belt - you can't wear
it out - its for 10,000 hours or more.
Sincerely. David Blanton."
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Australian Gliding March 1990
PROGRESS CONTINUES
ON WINDSOR ENGINE
There has been further progress on the
preparation of the Ford Windsor engine for
installation in a Pawnee tug.
During February, dynamic tests on the
engine were carried out on a lesl-hed al
Mordialloc. Melbourne.
Satisfactory results from these lesl will
lead to the engine being taken to Euroa
where it will be fitted to a single-seater
Pawnee glider tug and subjected to ground
testing.
If the installation proves to be satisfac.
tory, the Windsor-engined tug will be taken
to Benalla where flight testing will be car-
ried oul.
The assessment program for the Wind-
sor engine by the GFA has been held up
for several months while a single-seater
Pawnee has been prepared.
Earlier plans to test the engine in a two-
seater Pawnee had to be shelved when it
was found that two-seater Pawnees had
potential problems with the location of the
centre of gravity which could have result-
ed in a hazard for pilots.
There are indications that a worldwide
interest has developed in the possibility of
using the Ford Windsor engine. originally
designed for use in motor vehicles, to power
glider tugs and other light aircraft.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Australian Gliding June 1991
PROGRESS REPORT
Ford V6 Engine for Glider tug
The conversion of the Ford V6 engine
and the bench testing program are com-
plete. While this program has taken some
considerable time, the end result is pleasing.
Considerable modifications were carried
out on the engine and manifold system to
achieve equal fuel/air ratio and distribu-
tion to each cylinder, a problem peculiar
to most V-type engines running in the
higher rpm range.
With this fuel equalisation problem
solved, we have correct mixtures and tem-
peratures to every cylinder. an important
factor in the life of valves and fuel
economy.
Dyno testing was carried out for many
months and the engine is performing
satisfactorily.
The horsepower developed at the intend-
ed running speed of 4800rpm (which is
600rpm below the manufacturer's red line)
is 190hp with 208 ft/lb of torque.
These figures are very close to the
Lycoming 0-540 as fitted to the 235 Pawnee
at 2450rpm. The V6 will run at twice the
rpm of the Lycoming on a 2:1 reduction
drive.
Note:- The Lycoming 0-540 engine, as
fitted to most Pawnee 235s. develops 235hp
at 2575rpm (red line). At 2450rpm, which
is the rpm attained using the standard prop
while towing at 65-70kt. it develops 195hp.
Hopefully, the performance will only be
marginally less than that of the Lycoming
but we must not lose sight of the fact that
the object of this project was to gain econ-
omy not performance.
Lycoming publications show a fuel con-
sumption of 83 litres an hour, full throttle
at 2400rpm.
The V6 on dyno tests, full throttle at
4800rpm, showed a consumption of 59
litres an hour.
Costs of Avgas an hour, L.ycoming (full
throttle) $64
Costs of Mogas an hour. V6 (full throtlle)
$34
A further advantage of the V6 is the
negative throttle setting obtainable during
decent as against the considerable throttle
setting necessary with the Lycurning. thus
gaining further fuel economy.
Engine overhaul costs:-
z Lycoming (2100 hrs) $l5000 maximum
z V6 (1000 hrs) $ )3000 maximum
The engine is now at David Reilly's
workshop at Tocumwal undergoing fitment
to the Pawnee. This work is being carried
out under the guidance and supervision of
Mike Burns, who has closely monitored the
development program since its inception.
Progress reports should be more frequent
now that the engine developmenl and bench
testing are complete.
This report appeared in Nov 1991 issue of
Australian Gliding, the official journal of the Gliding Federation
of Australia
The GFA can be reached at :-
130 Wirraway Rd.
Essendon Airport
Victoria 3041
AUSTRALIA
Tel +61 3 3797411
Fax +61 3 3795519
(Note that this has been scanned in from the journal so please
excuse any funny format)
A report prepared for the 1991
GFA annual council meeting by
Dave Sharples
Auto-tug Pty Ltd
It was October 1988 when we decided to
proceed with a conversion of a water-
cooled automotive engine for glider tugs.
We purchased what was supposedly a
fully modified engine and reduction drive
from the USA. This was done because of
reports that the engine had been success-
ful and six years of development had gone
into the project.
What we got was a heap of rubbish. The
details are now history. Suffice it to say not
one modification done by the US compa-
ny was a success.
A total redesign has had to be under-
taken and we are now where we were sup-
posed to be when the engine arrived from
the US three years ago.
The reduction drive. which could be
described as the heart of the conversion, is
almost completely useless. We are now con-
templating whether to scrap the whole
reduction drive and redesign again or to
spend money on what we've got to make
it at least suitable for the testing program.
This is the last modification or rebuild
that has been done on all the US compa-
ny's items.
The only item that has not needed a rede-
sign is the camshaft and that was designed
outside the US organisation. They only fit-
ted the thing. Needless to say we have now
severed all contact with the company.
Apart from the delay and the unproject-
ed costs involved in all the rework required.
we have learnt a lot and know much more
about the whole program including costs
of the necessary modifications, perfor-
mance and projected maintenance costs
than we would have had we not been
through this exercise.
The economics of the V6 are very en-
couraging. The more we look into it the
more attractive it becomes.
Some comparisons are:-
Fuel
The Lycoming 0-540 uses 84 litres per
hour fuel consumption full throttle at 2400
RPM.
On descent at 2200 RPM and a throttle
setting of. say, 22 in Hg the consumption
is 47 litres per hr. (see the Lycoming graph)
The V6 at 4800rpm (2400 prop speed)
showed 59 litres per hour consumption full
throttle on the dyno test.
The V6 descends at nil throttle, whereas
the Lycoming has a considerable throttle
opening and a high rpm for at least a large
part of the descent. The saving in this area
is unknown but could be deemed to be
considerable.
z 0-540 fuel usage per hour (full tow cy-
cle) 65 litres @ .86c $SS.90
. V6 (not allowing for improved des-
cent) 45 litres @ .61c $27.45
z Approx saving in fuel alone $28.45 ($4
per tow)
Maintenance
We have fully reconditioned the V6 in-
cluding re-bore. crank grind. new valves,
springs, all bearings and pistons, all hold-
ing down bolts etc and fully balanced the
engine.
It is highly unlikely that it will be neces-
sary to go to this extent with each o'haul.
The cost of this major job was under
$3000. Compare this with the Lycoming at
anything from $16,000 to $25,000 with a
"top" o'haul during that period.
Note. It is envisaged that the V6 will be
majored at 1000 hrs. whereas the Lycom-
ing has 2000 hrs.
Saving per 100 hrs is $900 ($1.20 per
tow).
Expenditure to date
Purchase of original engine and
reduction drive $7585
Development costs. engine o'haul,
dyno testing etc. $6560
Admin costs $4921
GFA contributions to cost of
development program and new
propeller $8352
$27,418
Future cost estimates
CAA charges $2000
Geoff Young. Reg. 35 charges.
etc. 2000
Cowl manufacture & installation 1400
Engine mount fabrication 900
Cooling system fabricate/install 1000
Additional instruments 750
Fabricate/install engine controls 1150
Sort out and hook up elect. sys. 1150
Fabricate/install exhaust system 750
Fabricate/install fuel system 750
Fabricate/install intake system
air filter. hot air box, modify
manifold and carby system 1400
Rework reduction drive and install 5000
LAME charges for supervision 850
Weight and balance 500
Fuel for testing program 1500
M. Burns, Supervision during
whole project, design and
engineering. necessary reports and
liaison with CAA, car mileage etc. 5000
Insurance 1600
Total $27,700
Had we received what we expected ini-
tially from the USA. this project would be
up and running well before now and
without the costs described in the first
schedule.
Until now it has not been possible to es-
timate the overall cost of the program as
no one would have ever imagined the en-
gineering difficulties encountered.
The more we went into it the more
defects we found with ever-increasing costs.
Then a situation was reached where it
was not economically possible to disband
the project. In short we reached a point of
no return.
There is some satisfaction in considering
that we are far further advanced in three
years than the US company in their nine
years of development.
We have employed a full-time mechani-
cal engineer to complete the installation un-
der supervision starting 23 September.
Subject to no unforeseen holdups on the
reduction drive and further financing we
estimate being very close to applying for a
permit to fly in December this year.
For the first time. the project is now full
steam ahead.
An application has been submitted to the
Government for financial assistance for
research and development through the dis-
cretionary grant system.
Should this application fail, finance will
be required to complete the project.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Reprinted from "Australian Gliding"
November 1994
Original article by Dave Sharples
Kingaroy's Pawnee VH-CTA. sporting its converted Ford V6 engine. first
new on Dec.11 1992 Since then it has flown in excess of 65 hours and apart
from the expected adjustments and minor modifi- cations in the initial
stages its reliability. performance and economy has exceeded expectations.
Take off perlormance is quite acceptable . The ground run Prom chock to
sepa- ration measured 85 metres on a 35 degree Celsius day. The climb to
2000 ft was timed at 1 minute 25 seconds (not towing).
We have completed dozens of full throttle climbs to 5000ft in less than
four minutes and Mike Valentine achieved one to 9000ft. The engine
performed perfectly and no defects were apparent during these climbs.
The performance matches that of the 235 Pawncc as the V6 swings the
standard 235 Pawnee prop (McCauley 8254) at thc same RPM as the Lycoming
on climb at 65 knots.
What is amazing is the fuel cconomy. I ncw it for four hours and landed
with an hour to spare. This shows arond 27 litres per hour at cruise,
although several climbs to 5000ft were achievcd during that period on
mogas. The tank capacity is 150 litres.
A tow to 2000ft (Blanik. 2 up) and return was timed at slihtly less than
5 minutes. Depending on ground efficiency 1O tows plus per hour are
possible with an estimated maximum consumption of 35 litres of mogas.
This engine is particularly suitable for towing The climb performancc is
ade- quate. with no adverse effect when the throttle is fully closed upon
glider release. The descent is something we are not accustomed to:Just
close the throttle when the glider releases. spccd not above 80 knots. and
you`ll be on the ground before you realize what has happened.
I found that a trickle of power arrestcd the rate of descent enough to
plan a good circuit. and gave more time for lookout. The nose-down
attitude right from the point of release gives excellent vision. The 80
knot descent is far more comfortable on the pilot and airframe, especially
when thermals are active.
The coolant tcmperature varies only 10 degrees C throughout the entire
towing cycle.
More tesling and experience is necessary before handling recommendations
are fully compilcd.
Apart from the operation of the cngine the aircraft flies normally like
any other Pawnee. The propellcr position and the thrust line are
unaltered. and as stated the propeller spins at the same RPM as the
Lycoming.
It must be remebered that VH-CTA is a prototype. Much has heen learned
since the project started. The "production" model will he a much improvcd
version as we economized as best we could on the original until we had
proof of concept.
With engine overhauls and parts costing a fraction of those of the
Lycoming 0-540 together with the constant worry of cracking pots
eliminated and with fuel consumption greatly reduced. the prospect of
bringing glider towing costs to an acceptable level is very real.
The testing program is being conducted at Tocumwal under the watchful
eye of Mike Burns. It still has a long way to go.
If all goes to plan the conversion pack- age should be availuble towards
the end of 1994.
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
These reports appeared in
Australian Gliding,
the official journal of the Gliding Federation of Australia
The GFA can be reached at :-
130 Wirraway Rd.
Essendon Airport
Victoria 3041
AUSTRALIA
Tel +61 3 3797411
Fax +61 3 3795519