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Old 6th Sep 2019, 09:45
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jimjim1
 
Join Date: Oct 2007
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Posts: 640
Originally Posted by pattern_is_full View Post
JetCat P-series microturbojets run from $2500-ish (5.5 ftlbs P20-SX model) to $12000 (89 ftlbs - P400-PRO model, as used (x4)
JetCat RC Turbine Jet Engines - Chief Aircraft Inc. - Chief Aircraft Inc.
Thrust is measured in lbs. No feet involved.

Well kind of in lbs - this piece of wiki should make it all clear - as MUD
"The pound of force or pound-force (symbol: lbf[1], sometimes lbf,[2]) is a unit of force or weight used in some systems of measurement including English Engineering units
[a] and the Foot–pound–second system.[3] Pound-force should not be confused with foot-pound, a unit of energy, or pound-foot, a unit of torque, that may be written as "lbf⋅ft"; nor should these be confused with pound-mass (symbol: lb), often simply called pound, which is a unit of mass."

It like a Monty Python sketch - I recommend going metric on this one if you want to get closer to what is going on. Indeed the manufacturers use the SI (International System of Units)unit of force (Newton) as their primary statement of the engines capacity to do something useful..

JetCat P20-SX micro turbine for small model jets with a thrust of 24 Newton or 2,4 kg
JetCat P20-SX Micro Turbine with 24 Newton ,5,25 Lbs ( 2,4 Kg) Thrust.

What this means is that the engine above (P20-SX) will just barely hold a 5.25lb bag of potatoes off the ground, using a suitable system of frictionless bearings, pulley and weightless cable so that the engine is not supporting itself or its fuel etc.

Last edited by jimjim1; 6th Sep 2019 at 09:58.
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