Hi,
    This idea of an autopilot landing system just popped up in my mind, and
other details came almost immediately. I thought why hasn't anyone done it
before? The runway is something like 10m X 50m. GPS is used for
longitudinal/latitudinal positioning and preferably velocity measurement,
the aircraft would have a GPS receiver onboard, and 2 other GPS receivers
would sit on the both long ends at center of the runway, it's something akin
to differential GPS to provide better accuracy. Height measurement is done
by a ultrasonic transceiver or maybe GPS, are they accurate enough? And
pitch and roll is sensed by a pizeo gyroscope.

How feasible is this concept?

Regards,
Tan CC

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