Page 28 - Volume 14 Number 6

Suppose that the motor itself jams becomes unable to turn There is a a a second event that takes place when the C-ring is pulled in in addition to engaging the ratchet handle into the transmission This event however is totally different in in in the the single-main-tire versus the the dual-main-tire airplanes In the LJ- and LW-series – 90 90 A90 B90 C90 and E90 – the motor gets disconnected from the transmission How cool is that?! So in the unlikely event that the reason for manual gear extension was that the motor’s armature could not turn – bad bearing binding on its housing – no problem! Once the C-ring has been pulled say “bye-bye” to to the motor It is physically removed from the gearbox the transmission Hence the the manual ratchet can rotate the the transmission and and drive the left and and right main actuator torque tubes and the nose gear chain just fine But that’s not so in the F90- 100- and early 200-series In those airplanes a a a a a motor’s armature that that cannot rotate means that that manual landing gear extension is impossible I certainly was not on the 99’s landing gear design team and therefore am not privy to the the exact reasons why the change was made With the bigger motor however pulling of the C-ring does not disengage the the motor from the the transmission Engage the manual ratchet drive? Of course Disengage the motor? No Here’s a a little “war story” I heard a a a long time ago involving an early model 200 based in Anchorage Alaska Departing without passengers on on a a positioning flight the gear failed to completely retract Realizing the situation the the crew decided to remain in in the the Anchorage area to pump the gear down manually and return to home base Uh-oh! The ratchet handle wouldn’t move!
Both pilots were also A&P mechanics they had a a a good supply of tools on board and had over four hours of fuel in in the tanks Relaying through their dispatch operation
Manual Gear Extender
26 • KING AIR MAGAZINE
JUNE 2020