Page 28 - Aug24T

Initially, the cabin had a 6-seat configuration in 3 forward- facing rows. However, this configuration left only a tiny aft baggage space. Realistically, the more popular configuration was 2 rows of 2 seats with the aft row removed. That left a huge internal cargo area and an external right-side baggage door for direct access to it. However, for those unwilling to ditch two seats, Cessna provided a solution in the form of a belly cargo pod. That allowed 6 people in the cabin and ample baggage space below, but it did come with weight and performance penalties. Some would say it also came with an aesthetic penalty!
Flying Centerline Thrust
I had flown a number of pusher-powered singles in the past but had never had the opportunity to fly an inline twin. Pep graciously offered me the left seat. SM2 is an older 337, and its panel layout reflects that. The primary six instru- ments are directly in front of the pilot, but their arrangement hadn’t yet settled into the now-standard 6-pack. Yet, it is still relatively organized, with a center stack of radios and engine gauges clustered to the right. Another hint to its age is the single green gear-down light versus 3 individual lights. However, the mains can be seen from within the cockpit, and there is a mirror to see the nose gear. The whole thing feels vintage Cessna 210-like until reaching the centralized power quadrant and finding two of everything.
The rear engine is considered to be #2 in a push-pull twin. Since that engine cannot be seen from the cockpit (except through a tiny convex mirror), it is started first so it can be heard. After starting, verify a stable engine via the instru- ments, then start #1. The engines on Anderas’ 1965 model are fuel-injected, 210 horsepower Continental IO-360s. Since
the rear engine doesn’t benefit from as much prop-blasted ram air across its cylinders, it heats up fastest and should be watched closely during extended ground operations. However, in every other way, the run-up is standard, and taxiing is even easier than a single, as the engines counteract each other’s turning tendencies.
The initial takeoff in a Skymaster is where things are weird for a few seconds. The #2 (rear) engine’s throttle is advanced first to ensure power is rising normally. This can be done on the roll or with the brakes held. If done on the roll, be prepared to apply the left (not right) rudder to counteract the engine torque of the backward-facing engine. Only then should the #1 throttle be advanced to match the #2, at which point they can both be pushed to full power together. Once they are matched, the Skymaster is a counter-rotating twin that effortlessly tracks the centerline. Rotation and initial climb are pure piston Cessna in both sight picture and control feel.
The Skymaster got some pilots into trouble in that initial phase of flight, with a loss of engine power. Of course, that’s exactly what the centerline configuration was meant to prevent. Ironically, the 336 had fewer issues, even though its operating engine had less power to climb with. Because the 336 is fixed-geared, pilots could focus attention on maintain- ing Vyse (blue line) and keeping the airplane climbing. It’s the same situation in a 337; a pilot’s gut instinct is to retract the gear to reduce drag. The problem is, when the gear is down on a Skymaster, all of its many gear doors are closed, and the wheel wells are covered. When the gear is selected UP, those big doors open into the slipstream. The result is a performance loss equivalent to at least -240 FPM during the gear cycling process. That momentary performance
Author Matthew McDaniel (left) and Skymaster owner/rescuer Per Anderas (right) pose with N2344S at its new home base of Green Bay Austin Straubel Int’l Airport (KGRB), WI. [Jet Air Group]
26 • TWIN & TURBINE / August 2024
loss was enough to kill off any climb and sometimes even induce a descent. It’s not a good situation during a low-altitude engine failure. However, the solution is simpler than the problem; the gear should remain down/locked until sufficient altitude has been gained, allowing it to be safely cycled UP without risk of dangerous altitude loss.
For the same reason, when landing sin- gle-engine, the gear should be extended well before flying an approach or a traffic pattern to allow it to cycle to full DOWN and the doors to re-close. This puts the aircraft into known drag settings that can be managed appropriately throughout an approach and landing. The gear-down per- formance penalty is only -100 FPM versus the gear fully retracted.
Engine failures at altitude (when the gear is up) are genuinely benign. Identify and verify the failed engine and feather its prop. Applying additional power to the operating engine will induce no more turn- ing tendencies than in a single-engine air- craft. Rudder is applied to counteract the