Asked Questions About the BTE Double Whammy
Q: How fast does it go?
A: It's pretty darn fast! I have no way of measuring it, but my best
guess is that top level speed is in the 125-130 mph area. That's smoking
right along for a model with fixed gear and big wheels. Couple that speed
with the incredible noise and it's quite a show.
Q: Isn't it hard to start one Dynajet, let alone two?
A: Dyanajets can be temperamental, but they will start fairly quickly if
the fuel system is set up right. One trick we take advantage of is that a
Dynajet will start easier if it's warmed up. The normal start procedure
for the DW is to start one side, let it warm up, and shut it down. Then
we start the cold engine and go back to the warm one. Typically, the two
engines start and the model is released in a matter of 5-10 seconds.
Q: Why is there metal on the sides of the fuselage?
A: Pulsejets get hot - very hot. If you let a Dynajet run static for 15
seconds or more it will begin to glow red, then orange. The thin aluminum
is there to protect the wood fuselage from the heat. The best way to keep
the engines cool is to get them moving; that's why it's important to start
them quickly and get into the air.
Q: How do you land that thing?
A: Dynajets have no throttle, so every flight is made at full power and
every landing is made dead-stick. The DW is an amazing glider. I enjoy taking
it to altitude near the end of a flight and shutting down the engines with the
transmitter. During the glide, its fun to continue doing aerobatics, trading
altitude for energy like Bob Hoover, then trying to bring her in at my feet.
Q: What happens if an engine quits?
A: We've only had one flameout, on the model's second flight. And it was at the
very worst moment - right after takeoff. The DW wiggled a bit and kept right on
going. It doesn't have a rudder, but it wasn't needed. The model was designed with
a profile aft fuselage to keep the engines as close to the centerline as possible.
Q: Where do you fly the Double Whammy?
A: You can't fly pulsejet-powered models just anywhere. They make so much noise
that you could lose a club field in one flight. We like to take our models out to
dry lakes in Nevada where you can't bother anybody, hit anything, or start any fires.
You also have a limitless runway, which is nice for emergency landings. If I don't feel
like making the long drive to the dry lake, I can always fire up the DW in Real Flight!
Q: Is BTE going to make a kit?
A: No. But, but if you feel like a challenge, plans are available.
To Double Whammy Page