Macboffin thanks a lot but initially when we have capability of designing of our own then why do we need buy a stuff. See for example in J.D.Andruson's "Aircraft performance and design" he clearly explains about the normal aircraft like Cessna aircraft. So in case of VTOL it's a head breaking task. Thereby, do you have any proper guide line for designing a VTOL aircraft.
Maybe you could get a few ideas from this UAV(Panther by IAI).
Thanks Bim, but do you know the tit-rotor concept, at what gear ratio do it turn.
A lite efficient airframe and tricopter motor arraignment. Two front motors tilt 90 deg for forward or 0 for hover flight. Tail motor is shut down for forward fixed wing mode. Need to control attitude during transition from hover to forward flight. I have thought a lot about this, done some sketches and calculations. Plane/Copter or Copter/Plane depending on if you are taking of or landing.
Greg, transitional flight modes are the achilles heel of every VTOL aircraft, even conventional helicopters. This is where the Osprey is most vulnerable to be sure, with the added loss of pitch control as the nacelles are moving.