Page 17 - Nov18

or shutdown in flight: Even though autofeather has worked perfectly and has feathered the propeller very expeditiously, go ahead and feather it manually yourself. Pull that propeller lever fully aft! Why? Two reasons: First, it reinforces the importance of that critical step when flying King Airs or other propeller-driven twins that do not have the autofeather system. Second, it prevents the propeller from unfeathering itself!
You see, as the “Engine Shutdown in Flight” cleanup checklist is completed, the pilot is directed to turn off the Autofeather switch. Doing that removes power from the Autofeather Dump Solenoid and it goes to its Normally Closed (N.C.) position, shutting off the path through which prop oil has been released back into the engine. That 10-20 RPM rotation is enough to allow the prop governor’s oil pump to start refilling the prop dome with oil, bringing the blades out of feather, toward lower pitch and lower blade angles. As soon as the blade begins to move, there is less rotational resistance so the prop starts turning faster and supplying more oil. It is a self-perpetuating event and the blade angle keeps getting smaller at an ever-increasing rate. Before we know it – wham! – the propeller is back at maximum speed!
Where did all this drag suddenly come from?
The same thing will happen if the pilot verifies the suspected dead engine by pulling its power lever back but then fails to push the lever forward again. Remember that both power levers must be
well-advanced to activate the autofeather arming switches inside the power quadrant. Pulling either one back turns off autofeather to both sides.
My suggestions therefore are: (1) to continue your “Suspected Power Loss in Flight” memory items all the way to the end, including pulling the propeller lever fully into feather, and (2) leave the dead engine’s power lever either fully forward or matched with the other engine’s lever. By doing so the system will continue to be dumping prop oil even if we forget to turn the Autofeather switch off. It eliminates the “Where did that drag come from?” surprise ... and that’s a good thing! Another disadvantage of retarding the dead engine’s power lever to Idle is that it will trigger the landing gear warning horn to sound and will illuminate the red lights in the gear handle. Although the horn may be silenced, the red lights will remain on. Hence, there will be no way to ensure that the gear is properly retracted.
NOVEMBER 2018
If you fly a King Air in which the propeller totally stops rotation when feathered with a shutdown engine in flight, then your prop will not automatically unfeather itself. Nonetheless, I strongly suggest doing exactly the same procedures as I have advocated here. Why not stack the deck in your favor, especially since some day you probably will operate a model that exhibits some propeller rotation when shutdown?
LJ-2 Loses a Wheel
For a few months after I transferred from the Beech factory in Wichita to the Beechcraft West organization in California, I was based out of the facility in Fresno. One of Beechcraft West’s customers there ran a charter operation using a King Air 90 and a V35B Bonanza. The King Air was the second one ever built: LJ-2, a 1964 65-90 model, or “Straight 90.” By this time (early 1977) LJ-2 had received many upgrades and one of the more significant ones was reversing propellers, something the standard Straight 90 never had. The charter operation was quite busy and the King Air usually flew many times each week. A common charter saw her taking passengers down to KLAX to catch a flight out of that international hub.
The Great Central Valley of California is renowned for the winter presence of “Tule Fog.” Most mornings
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