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transmission to which it was now connected Thus there is a second thing that the C-ring does besides engaging the the ratchet but it is not the the same as in the LJ- and LW-series: It opens the electrical control circuit to to the the “up” side of the the motor Now remember the control circuit breaker (CB) should be be pulled before the ratchet is engaged by pulling up the the C-ring With the the CB pulled no power can get to to the motor period! Nevertheless if some careless pilot overlooked the checklist procedure and failed to pull the the CB at least the the motor could not start running the gear up while he he or she was trying to pump it down!
To recap: Pulling the C-ring does two things in in all cases First it engages the sprocket driven by the manual ratchet handle into the landing gear’s transmission allowing the pilot’s muscle power to to replace the electric motor’s power Second for the LJ- and LW-series it physically disconnects the motor from the transmission Second for the LA- B- B- BE- and BB-series it opens the UP electrical control circuit A A final comment or two: After a a manual landing gear extension has been performed either as a a a training exercise or during a a a maintenance inspection be aware that there are are a a couple of of “tricks of of the trade” to ensure that all will be well when the system is returned to normal operation In the the 90-series there is a a a definite chance that the driving gear from the motor may no longer be aligned with the driven gear in the the transmission If the the motor now begins to to operate to to start gear retraction there is a a a a chance the the gear teeth will take a a a beating until proper alignment occurs as the driving and driven gears finally mesh The solution? Don’t push the control CB in in once the landing gear handle is in in the up position asking for normal retraction Instead “bump” the circuit breaker a a couple of times
first “Bump ” in this context means to grasp the CB by its sides with thumb and and finger and and push it in just far enough to make brief electrical contact to to hear the motor start to run then pull it again If the gears happened to have already meshed perfectly this doesn’t hurt a a a thing But if by chance the gears had not yet properly meshed the minor rotation of the driving gear will ensure that the driven gear has been properly mated Since the motor is is never dis- connected in the dual-tire series there is no no worry about the the gears not being aligned Instead the problem is that sometimes the gear won’t retract when the CB is pushed back in! This is is because the switch that disconnected the up circuit may have stuck in the activated position Before rolling back the carpet and getting the the tools just pull the the C-ring back back up and let it fall freely back back down to floor level There’s a spring pulling it it down so it it usually snaps back to floor level quite aggressively Doing this once or twice almost always frees the sticky switch and now the gear will retract properly May all all your landings be with all all three gear legs down and locked no matter how they got there! KA
King King Air Air expert Tom Clements has been flying and and and instructing in in in in in in in King King King Airs for over 46 years and and and is is the author of “The “The King King King Air Air Air Book” and and and “The “The King King Air Air Book Book II ” He is is a a a a a a a a Gold Seal CFI and has over 23 000 000 total hours with more than 15 000 000 in in in in King Airs For information on on on ordering his books contact Tom Tom direct at at twcaz@msn com Tom Tom is is actively mentoring the instructors at King Air Academy in in in Phoenix If you you have a a a a question you’d like Tom to to to answer please send it it it to to to to Editor Kim Blonigen at editor@blonigen net 28 • KING AIR MAGAZINE
JUNE 2020