Parvez Dara, ATP, MCFI, SAFE Director
The other day, wanting to get some flying time, I decided to get checked out in a Piper Arrow. Aside from the similarities of the complex aircraft of a fuel injected engine, and retractable gear the two beasts are quite different.
Lets us take them apart one by one and compare the results. This is by no means a put down or build up of either one. It is merely a note on transition thoughts in the left seat effects on the pilot. There is definitely a need for a difference between the mind and the mental state.
The “big” Mooney engines are Lycoming TIO540 derated down to 270hp (Mooney Bravo a true turbocharged aircraft or TIO-550-G Mooney Acclaim-a turbo normalized version). The latter has twin Turbocharger and Innercooler built in front of the firewall, they also exact a hefty price in weight. The Mooney climbs at a nice clip reaching a comfortable 1200 feet per minute in the right circumstance. The Manifold is set at 36 inches and the RPM near redline around 2550rpm. It guzzles around 26 gallons in the climb. You can feel it getting light on its wheels wanting to break the surely bonds, as it transitions easily and with very little effort into the cruise climb mode. Retracting the gear is easy and the transition to “wheels up” takes 4-5 seconds. Trimmed, it is an easy-peasy state of affairs as the earth is left behind quickly. Decreasing the MP to 34/2400 in a cruise climb, the boost pump light flickers off. Cruise power setting is mostly at 30MP and 2400RPM with about 16 gallons per hour. Average speeds at max cruise setting is around 185-190 knots at 8000feet. The boost pump is linked to the throttle to the wall and easing it back shuts the boost pump allowing the mechanical fuel pump to take over.
The Piper Arrow is obviously slower because it is powered by a Lycoming IO360 at 200hp and not turbocharged. The instructor calls for a 25MP and 2500RPM as a cruising power setting and the engine sips around 10.5-11 gallons. It wants to run its wheels a little bit more on the ground and one has to gently heave it off the tarmac. It too feels light when the needle goes past the 60-65 knots of airspeed. The climb, as expected is a bit anemic and the climb rate factors in between 500-600 feet per minute. But climb, it does and remains steady till about 3000 feet or so, when the climb rate diminishes slightly. The max cruise speed at 8000 feet is around 138-140 knots. The Fuel Boost pump has to be manually switched on and off in both take offs and landing modes as well in changing fuel tanks.
Mooneys have the laminar Airfoil that love to fly. The Arrow has the trademark Hershey Bar wings, bulbous and not as relative wind friendly. But they are stable and do provide a better buffer against the potential ice formation. As both wings develops lift against the Relative Wing and Newton pushes from below and Bernoulli pulls from above, both airfoils seem fairly happy flying. But kill the engine in the air and the differences become quite stark. The Mooney wing continues to soars along wasting between 350-400 feet/minute of altitude as it transitions at Glide Speed down to the earth. The Arrow however loses 1400-1500 feet per minute at Glide Speed and looks for a landing strip close by. While Mooney gives ample time to think about the Insurance company, the Arrow demands immediate attention for safety.
The newer model Arrows are equally equipped with the “Glass Cockpits” like the newer Mooneys. The difference lies in the positions of the knobs. This understanding of knobology is what takes time. Pilots transitioning from one aircraft to another, no matter the age of the aluminum, need to develop a firm handle on where the various knobs are. This education in “knobology” is better served on the ground then in the air. A small but critical example; Mooneys have their Gear handle up on top of the panel space with a single green light indicating gear down state, while the Arrow I flew had the Gear handle under the yoke in the lowest part of the panel space with the “three green light” symbology determining the gear locked in place based on stimuli received from the limit switches within the wheel wells. Interestingly the “three green” are individual bulbs and in case of one not lighting up can easily be tested by substitution. Whereas the Gear System in the Arrow is the electromechanical version relying both on electric and hydraulics to move the pieces up and down, the Mooneys have electrical worm drive that retracts and extends. Both aircraft have limits of extension and retraction air speed limitations. The Arrow has a feature; which can be disabled when air work is being performed, the automatic gear extension when the airspeed declines below 105 knots.
Now here is another stark difference between the two aircraft I flew; the Mooney has a small lever placed in the middle lower quadrant of the panel with an indicator to show the flap status between Approach and Landing flap configuration. Oscillating between Flaps Up and Down is dependent on a flip of a switch. In the Arrow there is a handle-bar on the floor that is purely muscle mechanics and goes from 10 degrees to 40 degrees (barn doors category). Both mechanisms function perfectly. In the Mooney, a popped circuit breaker can render the Flap switch functionless (there is a mechanical feature for gear extension). The Arrow however is resilient. No need for electricity to apply, since brute strength is the modus operandi.
I enjoyed the flights in both the aircraft equally. Knowing the difference in characteristics and what to expect makes one adept at understanding what the airfoil, the engine and a plethora of electro-mechanical gizmos can do. It took me a half hour to close my eyes and sit in the cockpit imagining the location of various switches, circuit breakers and other locations of the Garmin 430, Transponder (GTX 327), and the second radio a KX150. The Mooneys I have flown have been with the Garmin 1000 Glass and also those with steam gauges. The locations of the “Six Pack” (non glass) are firmly placed in front of the eyeballs in both aircraft (standard).
The transition between the two aircraft was relatively easy, enjoyable and in both cases brought breathtaking views to behold-as it always without fail, does!
A few words of Advice:
So if you intend to transition to a different aircraft, either old or new, spend a few moments:
It is important as is in all aircraft to follow the Checklist for Preflight, since there are quite a few differences between any two aircraft.
Get comfortable in the cockpit.
Close your eyes and accurately place the various panel placed equipment.
Know the Lift characteristics of the Wings.
Know the engine function
Keep the Standard Checklist nearby and use it for Preflight, Take-Offs, Approach to Landing, Landing, Taxi and Shutdowns…Follow the checklist to the “T.”
Keep the Emergency Checklist nearby for Engine outs, Fires, Gear malfunction etc.
Get comfortable with the flight characteristics of the aircraft with an Instructor before going solo…there is always more than meets the eye.
Transitioning from a faster to a slower aircraft requires equal diligence as one from a slow aircraft to a faster one. The anticipatory times are different in flying the “other” one.
Please Fly With Understanding…Fly SAFE!
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