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Ireceived the following question and thought the answer would be of interest to King Air magazine readers.
I was wondering if you could elucidate a bit upon the thinking behind Beech going to a T-tail on the King Air 200. If I remember correctly, the 100 series had a conventional tail. So what were Beech’s reasons for going to the T-tail on the BE200? What are the advantages and disadvantages of the T-tail?
I am glad this question was asked because not many pilots know the reason for the T-tail design.
The 100-series tail was the same tail first used on the Beech 99, the 15-seat, unpressurized, commuter airliner. When the cabin was stretched as much as it was—making a turbine-powered Queen Air into a 99—the prototype flew with much the same tail as on the 90 series, using fixed horizontal stabilizers and elevators with trim tabs. Alas, they could not achieve a long enough center of gravity (CG) range to suit the longer airplane with that system. So, the Beech engineers went back to the drawing boards to come up with a solution.
In the resulting design, the elevators have no trim tabs and, instead, the whole horizontal stabilizer pivots near the rear and an electrically-driven jackscrew moves the leading edge up and down. It is like a Piper Cub or Cessna 180, but without any manual system, only an electric Main and Standby system, with a clutch arrangement to allow either to work should the other jam.
When you next see a 100, A100 or B100 on a ramp, notice the huge span of the stabilizer—it is one massive tail! In fact, do you realize that the top of the 100’s vertical stabilizer is a few inches higher than the top of a 200-, 300- or F90-series T-tail? Surprising but true.
Next came the 200, which had the same fuselage/cabin as the 100 but with 850 shp per side (versus 680 shp for the 100/A100) and the centerline of the engine moved 25 inches outboard. The appropriate propeller to handle the higher horsepower had enough additional diameter to hit the fuselage if the existing 90/100 center section was used and the tip clearance with the ground was too small. So, if Beech had to move the engine both outward and upward, the decision was made to really move it out—much more than the minimum requirement—to give extra clearance between the prop arc and the fuselage, making the cabin quieter.
The T-tail on a King Air 200.
NOVEMBER 2024
KING AIR MAGAZINE • 19
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