So the latest issue of Kit Planes had a Paul Dye article on his SubSonex. Interesting article. He makes it pretty clear that building and owning a SubSonex is pretty much of a vanity thing - it's not a good XC machine, for instance.
But that got me to thinking:
These little jet engines are coming down in price and increasing in performance and reliability.
Is a scale ME-262 with two of the SubSonex engines (PBS TJ-100 turbojet) at all feasible?
Can you arrive at a scale and weight where:
1) A sea level standard sized pilot can fit comfortably and
2) Can you increase the fuel capacity to make it a good XC machine
3) Can you make it a 6+/4- G aerobatic airplane without increasing weight
and what are the engine inlet issues with regard to aerobatics?
The very first crude calculation is thrust to weight:
Stock ME-262
thrust * 2 = 1,848
gross weight = 14,271
Thrust to weight = 0.26 - 0.28
Thrust taken from 109-004B
Production-series engines with reduced weight and strategic
materials.
SubSonex:
Thrust * 1 = 258.53 lb
gross weight = 1000lbs
Thrust to weight = 0.25852
Scale-262:
Thrust * 2 = 517.06
gross weight = 2000 lbs
Thrust to weight = 0.25853 (Obviously the same as the SubSonex since I doubled
both Values)
Similar thrust to weight. I wonder if one could get the weight down substantially? I think 2000 lbs is a conservative overestimate but I don't know that for sure. Certainly composites would
help with that.
But that got me to thinking:
These little jet engines are coming down in price and increasing in performance and reliability.
Is a scale ME-262 with two of the SubSonex engines (PBS TJ-100 turbojet) at all feasible?
Can you arrive at a scale and weight where:
1) A sea level standard sized pilot can fit comfortably and
2) Can you increase the fuel capacity to make it a good XC machine
3) Can you make it a 6+/4- G aerobatic airplane without increasing weight
and what are the engine inlet issues with regard to aerobatics?
The very first crude calculation is thrust to weight:
Stock ME-262
thrust * 2 = 1,848
gross weight = 14,271
Thrust to weight = 0.26 - 0.28
Thrust taken from 109-004B
Production-series engines with reduced weight and strategic
materials.
SubSonex:
Thrust * 1 = 258.53 lb
gross weight = 1000lbs
Thrust to weight = 0.25852
Scale-262:
Thrust * 2 = 517.06
gross weight = 2000 lbs
Thrust to weight = 0.25853 (Obviously the same as the SubSonex since I doubled
both Values)
Similar thrust to weight. I wonder if one could get the weight down substantially? I think 2000 lbs is a conservative overestimate but I don't know that for sure. Certainly composites would
help with that.