Aerial refueling system, apparatus and methods
View Patent ↗An aerial refueling system utilizes the full drogue-probe coupling event as a control parameter for hose control. A variety of different types of signal sending and signal receiving devices may be used to indicate a coupling event between the drogue and probe. A positive coupling signal may serve to trigger a hose reel actuator to take up slack in the hose 16.
1. Apparatus for an in-flight refueling system between a first aircraft and a second aircraft, the first aircraft providing fuel to the second aircraft while said first and second aircraft are both in flight, said apparatus comprising:
a) a drogue having inner and outer surfaces;
b) a hose having a first end configured to be mounted on the first aircraft and a second end connected to said drogue;
c) one or more trigger devices positioned at a predetermined location on said drogue;
d) one or more signal emitting devices on said drogue, said one or more signal emitting devices switchable between off and on positions;
e) one or more roller elements positioned on said drogue and biased radially inwardly toward the longitudinal axis of said drogue whereby movement of said one or more roller elements radially outwardly causes said one or more signal emitting devices to switch from one of said off and on positions to the other of said off and on positions and produce a signal; and
f) one or more signal receiving devices configured to be positioned on said first aircraft, wherein said one or more signal receiving devices is configured to receive the signal when a probe fitted on the second aircraft is fully coupled with said drogue,
wherein said signal is emitted only after said one or more signal emitting devices is switched from one of said off and on positions to the other of said off and on positions for a threshold length of time.
2. The apparatus of claim 1 , wherein said one or more signal emitting devices are one of LEDs, infrared diodes, radio or microwave emitters.
3. The apparatus of claim 1 , wherein said one or more signal emitting devices and said one or more signal receiving devices are modulated at a predetermined frequency.
4. The apparatus of claim 1 , wherein said one or more trigger devices comprise one or more switches changeable between open and closed conditions positioned at the predetermined location on said drogue, wherein said one or more switches are configured to change from one of said open and closed conditions to the other of said open and closed conditions upon said probe being fully coupled with said drogue.
5. The apparatus of claim 1 wherein said threshold length of time is about 50 milliseconds.
6. The apparatus of claim 1 wherein the apparatus further comprises:
a) the probe configured to be fitted on the second aircraft; and
b) a second signal emitting device comprising a light source and detector pair located within said drogue and having a line-of-sight that is configured to be interrupted upon said full coupling of said probe with said drogue and, upon interruption, is operable to emit a second signal.
7. The apparatus of claim 6 wherein said probe includes a probe tip configured to interrupt said line-of-sight upon full coupling of said probe with said drogue.
8. The apparatus of claim 7 wherein said probe includes a narrowed ring element located proximally of said probe tip, and wherein said roller elements bias inwardly and locate within said narrowed ring segment only upon full advancement and coupling of said probe within said drogue.
9. The apparatus of claim 8 wherein said probe tip is spaced apart from said narrowed ring segment a distance which causes said probe tip to interrupt said line-of-sight only when said roller elements have located within said narrowed ring segment.