Also included in this column:
• Jets Over Kentucky
• Don’t add fuel to the fire!
December 2010 129
[[email protected]]
Radio Control Jets Jim Hiller
Experimenting with EDF jet power
Rod Snyder, a longtime IJMC competitor, put in quite a few flights
with his new Skymaster F-16 at Jets Over Kentucky. The colors
are amazing!
Bob Bush, a US IJMC team competitor, masterfully built and flew
this beautiful BVM Jets F-100.
Bill Thatcher (L) at Jets Over Kentucky with his Fly Eagle Jets 1/5-
scale F-86 powered by a Jet Central Rhino turbine. Bill is a quality
modeler.
This summer i was introduced to large electric-ducted-fan (EDF)-
powered aircraft, so I’ll give you a turbine-power flier’s take on big
EDFs.
I fly with John Fulmer, and he has converted an old ducted-fanpowered
Super Eagle to a Byron fan with an XPS “soda can” motor
powered by a 10-cell battery. This jet weighs almost 20 pounds, but it
is performing impressively with the simple 10-cell setup.
Another terrific model is “Billy D,” a grand old Byron F-16, which
was beautifully built and painted and is powered by a Dynamax fan
with an XPS soda can motor.
All of that got me going, so I pulled out my old ducted-fanpowered
Usher F-100 that Dick Driftmeyer built and handed it over to
Bill White, who is one of my club’s electric gurus.
He put a good old Dynamax fan in the F-100, powered it with a
Neu 1527/1.5Y motor, and installed a Castle Creations 140-amp speed
controller. Battery power is supplied by a pair of five-cell 5000 mAh
30C XPS packs. The fan pulls 118 amps at full power, showing almost
3,900 watts—all in a model that weighs slightly more than 14 pounds
with batteries.
I’m no expert at this electric thing, but Bill assured me that he
installed a good setup. So off we went to fly the model, and it works!
Performance on takeoff is good; there is plenty of power to climb
clear of the trees and keep going. The motor fan setup is nice for this
jet.
Flying the F-100 is fun. I especially like diving out of the sky to a
low pass, with no power, letting the airframe whistle by, and then
getting on some power and flying away. It provides for a neat sound
and experience.
But, alas, this electric thing isn’t all roses. Flight times are limited.
We restrict ours to approximately 4 minutes, from start of takeoff to
wheels on the ground.
Then you have to spend the whole flight thinking about how to
manage the available battery power. At full power that battery would
be drained to 80% in less than 2 minutes. Flying the F-100 has been an
12sig5x.QXD_00MSTRPG.QXD 10/22/10 8:32 AM Page 129
education in battery management and
understanding how to get the most from them.
We have learned that the time spent at full
throttle is when the batteries heat up. One time
we got them up to 140°—the magical number
that one should not exceed.
That was done on a flight during which we
ran the system hard, including a full-throttle
pass immediately before landing. We figure
that this full draw with the packs already run
down is what generated the heat. The batteries
took 4800 to get back to a full charge.
During a typical well-behaved flight we
used full throttle only on takeoff and
performed the rest of the flight at 50%-75%
power. The model attains fast cruising power,
and then uses the momentum to return to
altitude for the turns. With this technique we
have flown for more than 4 minutes and
landed with battery temperatures at 110°-120°.
Experienced EDF modelers will tell me
that we are battery-limited and that it is time to
step up to the latest battery technology. The F-
100 has room for more batteries and the power
to handle a heavier battery setup, so I might
budget for new batteries for next season.
In the meantime we are having fun
cruising around with the old model—
quietly. It has been a great model for Bill
to use to step up to high-performance jet
flying without the intimidation of a
turbine. It’s almost as fast but not nearly
as loud.
EDF power provides for great experience
in the latest expanding technology, but it lacks
the sound and fury of jet aeromodeling.
Performance of EDFs is getting to be great
and our speed and vertical flight are good, yet
we are still a year or two behind in battery
technology; you know it only gets better.
As I mentioned, flight times are limited,
which leads to flights during which you spend
a lot of time focusing on throttle management.
It makes a big difference in flight times and
battery temperature.
There are many ways to tackle EDFs, and
now Bill White and I have one.
This was my first year to attend Jets Over
Kentucky at the Lebanon-Springfield
Airport in Lebanon. What an event!
A total of 116 registered pilots took 263
jets for one great week of flying, July 4-11.
Yes, that’s right—a full week. You can go
early and fly often before the weekend crowds
show up.
Lewis Patton did a great job with this event,
and the community and airport personnel
stepped up along with him to make everyone
feel welcome. Lewis lived at the airport from 7
a.m. to 10 p.m. each day, no kidding, working
to keep things moving and solving problems as
they came up.
The facility was almost perfect for a jet
event. There was plenty of paved areas for
parking, start-up, and campers, plus a large
hangar for overnight model storage.
This event attracts some of the best jet
modelers in the country and Canada too! This
year’s weather helped make it a great week of
flying, camping, and hanging with fellow
aeromodelers.
The sponsors get behind this fly-in. This
year they even put up for almost 18,000 square
feet of tent area for the pilots. The pilot raffle
featured some unbelievable items, ranging from
top-end radios to turbines and much more.
If you love jets, either as a pilot or a
spectator, Jets Over Kentucky is a great event
to attend!
Let’s get back to turbines and how to deal
with a failed start. Not the simple one, but the
one that includes flames!
Many of us experience errant flames when
things go wrong during start-up, so let’s
prepare for it. At a jet meet this year I saw
three fires. The pilots and crews handled two
of those poorly, and one got scary.
Always have a fire extinguisher with you
on the flightline. It’s a simple thing to do.
That bad start will probably happen; we
just don’t know when. One situation in which
this can happen is during a hot start caused by
excess kerosene in the turbine. As the engine
accelerates during start-up, excess kerosene
blows out the back end, where it combines
with oxygen to create a flame.
When that scenario happens, shut down
the start sequence and give the flames a quick
blast of the CO2 fire extinguisher. The fire
usually goes out immediately, and without the
turbine spewing out more kerosene there’s no
fuel to burn.
Don’t get excited when you see flames.
Deal with it. And whatever you do, don’t fan
the fire with a leaf blower; adding oxygen to
the fire doesn’t help.
130 MODEL AVIATION
The next situation is a bit more
complicated and tends to create the scary
moments, and that is excess starting gas in the
fuselage; i.e., propane. I experienced that this
summer on my BVM BobCat, which has an
externally mounted turbine.
The root cause of the excess propane was a
leaking propane valve. As the start sequence
initiated, the glow plug came on and lit the
propane that had collected in the turbine.
There was a bang, followed by a short shot of
flames coming out of the turbine.
I immediately shut down the start
sequence. Because the extra propane had
already burned off, the incident was over.
Fixing the leaking propane valve was
simple. I pulled it apart, cleaned out the dirt
that caused the leak, and have had no more
problems.
The next time I saw that happen was with
an internally mounted turbine, which poses a
new problem. Propane is heavier than air, so
in this situation the propane leak fills the
fuselage with gas, pooling in the bottom.
When you initiate the start sequence, you
hear a pop from propane igniting in the
turbine. Then the free propane settled in the
lower part of the fuselage is lit.
Again, handle this quickly and easily by
shutting down the start sequence and
administering a shot of the CO2 fire
extinguisher. With no oxygen the fire goes
out. And if you get to it soon, no airframe
components will have caught fire. Then you
merely need to assess the damage and cure the
problem.
Having completed that lesson, it’s time to
pack and head to Litchfield, Illinois, for
the IJMC (International Jet Model
Committee) US Team Qualifier for the
2010 Jet World Masters, followed by
Route 66 Jets. I love flying jets, having fun
across the country. MA
Sources:
BVM Jets
(407) 327-6333
www.bvmjets.com
Xtreme Power Systems
2440 N. Kiowa Blvd.
Lake Havasu City AZ 86403
www.xtremepowersystems.net
NeuMotors
(858) 674-2250
www.neumotors.com
Castle Creations
(913) 390-6939
www.castlecreations.com
Jets Over Kentucky:
www.visitlebanonky.com/events/kyjets.htm
Jet Pilots Organization
www.jetpilots.org
Jim Hiller
6090 Downs Rd.
Champion OH 44481
Edition: Model Aviation - 2010/12
Page Numbers: 129,130
Edition: Model Aviation - 2010/12
Page Numbers: 129,130
Also included in this column:
• Jets Over Kentucky
• Don’t add fuel to the fire!
December 2010 129
[[email protected]]
Radio Control Jets Jim Hiller
Experimenting with EDF jet power
Rod Snyder, a longtime IJMC competitor, put in quite a few flights
with his new Skymaster F-16 at Jets Over Kentucky. The colors
are amazing!
Bob Bush, a US IJMC team competitor, masterfully built and flew
this beautiful BVM Jets F-100.
Bill Thatcher (L) at Jets Over Kentucky with his Fly Eagle Jets 1/5-
scale F-86 powered by a Jet Central Rhino turbine. Bill is a quality
modeler.
This summer i was introduced to large electric-ducted-fan (EDF)-
powered aircraft, so I’ll give you a turbine-power flier’s take on big
EDFs.
I fly with John Fulmer, and he has converted an old ducted-fanpowered
Super Eagle to a Byron fan with an XPS “soda can” motor
powered by a 10-cell battery. This jet weighs almost 20 pounds, but it
is performing impressively with the simple 10-cell setup.
Another terrific model is “Billy D,” a grand old Byron F-16, which
was beautifully built and painted and is powered by a Dynamax fan
with an XPS soda can motor.
All of that got me going, so I pulled out my old ducted-fanpowered
Usher F-100 that Dick Driftmeyer built and handed it over to
Bill White, who is one of my club’s electric gurus.
He put a good old Dynamax fan in the F-100, powered it with a
Neu 1527/1.5Y motor, and installed a Castle Creations 140-amp speed
controller. Battery power is supplied by a pair of five-cell 5000 mAh
30C XPS packs. The fan pulls 118 amps at full power, showing almost
3,900 watts—all in a model that weighs slightly more than 14 pounds
with batteries.
I’m no expert at this electric thing, but Bill assured me that he
installed a good setup. So off we went to fly the model, and it works!
Performance on takeoff is good; there is plenty of power to climb
clear of the trees and keep going. The motor fan setup is nice for this
jet.
Flying the F-100 is fun. I especially like diving out of the sky to a
low pass, with no power, letting the airframe whistle by, and then
getting on some power and flying away. It provides for a neat sound
and experience.
But, alas, this electric thing isn’t all roses. Flight times are limited.
We restrict ours to approximately 4 minutes, from start of takeoff to
wheels on the ground.
Then you have to spend the whole flight thinking about how to
manage the available battery power. At full power that battery would
be drained to 80% in less than 2 minutes. Flying the F-100 has been an
12sig5x.QXD_00MSTRPG.QXD 10/22/10 8:32 AM Page 129
education in battery management and
understanding how to get the most from them.
We have learned that the time spent at full
throttle is when the batteries heat up. One time
we got them up to 140°—the magical number
that one should not exceed.
That was done on a flight during which we
ran the system hard, including a full-throttle
pass immediately before landing. We figure
that this full draw with the packs already run
down is what generated the heat. The batteries
took 4800 to get back to a full charge.
During a typical well-behaved flight we
used full throttle only on takeoff and
performed the rest of the flight at 50%-75%
power. The model attains fast cruising power,
and then uses the momentum to return to
altitude for the turns. With this technique we
have flown for more than 4 minutes and
landed with battery temperatures at 110°-120°.
Experienced EDF modelers will tell me
that we are battery-limited and that it is time to
step up to the latest battery technology. The F-
100 has room for more batteries and the power
to handle a heavier battery setup, so I might
budget for new batteries for next season.
In the meantime we are having fun
cruising around with the old model—
quietly. It has been a great model for Bill
to use to step up to high-performance jet
flying without the intimidation of a
turbine. It’s almost as fast but not nearly
as loud.
EDF power provides for great experience
in the latest expanding technology, but it lacks
the sound and fury of jet aeromodeling.
Performance of EDFs is getting to be great
and our speed and vertical flight are good, yet
we are still a year or two behind in battery
technology; you know it only gets better.
As I mentioned, flight times are limited,
which leads to flights during which you spend
a lot of time focusing on throttle management.
It makes a big difference in flight times and
battery temperature.
There are many ways to tackle EDFs, and
now Bill White and I have one.
This was my first year to attend Jets Over
Kentucky at the Lebanon-Springfield
Airport in Lebanon. What an event!
A total of 116 registered pilots took 263
jets for one great week of flying, July 4-11.
Yes, that’s right—a full week. You can go
early and fly often before the weekend crowds
show up.
Lewis Patton did a great job with this event,
and the community and airport personnel
stepped up along with him to make everyone
feel welcome. Lewis lived at the airport from 7
a.m. to 10 p.m. each day, no kidding, working
to keep things moving and solving problems as
they came up.
The facility was almost perfect for a jet
event. There was plenty of paved areas for
parking, start-up, and campers, plus a large
hangar for overnight model storage.
This event attracts some of the best jet
modelers in the country and Canada too! This
year’s weather helped make it a great week of
flying, camping, and hanging with fellow
aeromodelers.
The sponsors get behind this fly-in. This
year they even put up for almost 18,000 square
feet of tent area for the pilots. The pilot raffle
featured some unbelievable items, ranging from
top-end radios to turbines and much more.
If you love jets, either as a pilot or a
spectator, Jets Over Kentucky is a great event
to attend!
Let’s get back to turbines and how to deal
with a failed start. Not the simple one, but the
one that includes flames!
Many of us experience errant flames when
things go wrong during start-up, so let’s
prepare for it. At a jet meet this year I saw
three fires. The pilots and crews handled two
of those poorly, and one got scary.
Always have a fire extinguisher with you
on the flightline. It’s a simple thing to do.
That bad start will probably happen; we
just don’t know when. One situation in which
this can happen is during a hot start caused by
excess kerosene in the turbine. As the engine
accelerates during start-up, excess kerosene
blows out the back end, where it combines
with oxygen to create a flame.
When that scenario happens, shut down
the start sequence and give the flames a quick
blast of the CO2 fire extinguisher. The fire
usually goes out immediately, and without the
turbine spewing out more kerosene there’s no
fuel to burn.
Don’t get excited when you see flames.
Deal with it. And whatever you do, don’t fan
the fire with a leaf blower; adding oxygen to
the fire doesn’t help.
130 MODEL AVIATION
The next situation is a bit more
complicated and tends to create the scary
moments, and that is excess starting gas in the
fuselage; i.e., propane. I experienced that this
summer on my BVM BobCat, which has an
externally mounted turbine.
The root cause of the excess propane was a
leaking propane valve. As the start sequence
initiated, the glow plug came on and lit the
propane that had collected in the turbine.
There was a bang, followed by a short shot of
flames coming out of the turbine.
I immediately shut down the start
sequence. Because the extra propane had
already burned off, the incident was over.
Fixing the leaking propane valve was
simple. I pulled it apart, cleaned out the dirt
that caused the leak, and have had no more
problems.
The next time I saw that happen was with
an internally mounted turbine, which poses a
new problem. Propane is heavier than air, so
in this situation the propane leak fills the
fuselage with gas, pooling in the bottom.
When you initiate the start sequence, you
hear a pop from propane igniting in the
turbine. Then the free propane settled in the
lower part of the fuselage is lit.
Again, handle this quickly and easily by
shutting down the start sequence and
administering a shot of the CO2 fire
extinguisher. With no oxygen the fire goes
out. And if you get to it soon, no airframe
components will have caught fire. Then you
merely need to assess the damage and cure the
problem.
Having completed that lesson, it’s time to
pack and head to Litchfield, Illinois, for
the IJMC (International Jet Model
Committee) US Team Qualifier for the
2010 Jet World Masters, followed by
Route 66 Jets. I love flying jets, having fun
across the country. MA
Sources:
BVM Jets
(407) 327-6333
www.bvmjets.com
Xtreme Power Systems
2440 N. Kiowa Blvd.
Lake Havasu City AZ 86403
www.xtremepowersystems.net
NeuMotors
(858) 674-2250
www.neumotors.com
Castle Creations
(913) 390-6939
www.castlecreations.com
Jets Over Kentucky:
www.visitlebanonky.com/events/kyjets.htm
Jet Pilots Organization
www.jetpilots.org
Jim Hiller
6090 Downs Rd.
Champion OH 44481
