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Old 07-14-2023, 02:28 PM
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blackshire blackshire is offline
Master Modeler
Join Date: Jan 2009
Location: Fairbanks, Alaska
Posts: 6,507

Originally Posted by Gus
Seller took the link down until he checks on the shipping regulations.

Seems like a very nice fellow who was unaware of any restrictions on shipping motors less than 60 grams.

I'm trying to provide him some Canadian shipping resources.
Thank you for doing this, Gus. Recently, I've been looking longingly at my tiny stash of Dr. Z-made Rapier jet motors, hoping that another supplier of these Jetex-type (by function, and low thrust vs. long burn time) model aircraft motors will come along; if Hummingbird plays its cards right, it sounds like the new supplier! Also:

In addition to powering F/F model jets (mounted in bypass ducts, as was/is often the case with Jetex models, with basic operation not unlike that of turbofan engines, in order to [1] increase the thrust, [2] lower the aggregate jet efflux velocity to better match the models' typical flight speeds [by moving more fluid, but more slowly], and [3] to cool the jet efflux), these low-thrust/long-burn jet motors can also operate in "pure rocket mode," via the following means:

The Walter rocket engines that were being developed for the later Messerschmitt Me 163 Komet rocket interceptors had two chambers (see: ). The larger chamber was used for takeoff and climb, while the smaller chamber maintained the aircraft's high speed in level and/or much less steeply-climbing flight, at altitude, thus increasing the Komet's powered flight time over that of the single-chambered rocket engine-powered Komet variants. ALSO:

The Beechcraft AQM-37 Jayhawk target drone (see: , and ) also uses a two-chambered rocket engine (with a larger "boost" [accelerate] chamber, and a smaller "sustain" one), for much the same purposes the later two-chambered Walter rocket engines were to be used in the later Me 163 Komet interceptors. Firing both AQM-37 rocket engine chambers at once--and keeping both firing--provides faster, but shorter-duration, drone target presentation flights; firing both chambers at first, then soon shutting down the "boost" chamber, enables somewhat slower, but significantly longer-duration, drone target presentation missions. This allows more missile and gunnery practice--even by multiple crews in different locations--to be carried out against a single AQM-37. As well:

F/F scale models of the later Me 163 Komet variants--*and* of the various AQM-37 versions--could use the Jetex, Rapier, or Hummingbird jet motors in the "sustain" mode ("pure rocket mode," in non-bypass duct mounts), operating as true rocket planes. This could also be done with F/F scale models of the Northrop MX-324 (a rocket-powered flying wing glider, see: , and ), the U.S. M2-F3, HL-10, and X-24A/B lifting bodies, and the X-1, X-1A/B/C/D, X-1E, and X-2 rocket planes, etc. (Where needed, a flat metal strip "jetavator" behind the motor nozzle could maintain level flight under rocket power [this was done with a non-scale, late-1940s rocket plane model kit that used a fuse-ignited, skyrocket-type proprietary black powder motor], until the consumption of the propellant moves the model's CG forward, for a good glide).
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
All of my book proceeds go to the Northcote Heavy Horse Centre
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