The Training Wheel

The debate about where the middle wheel belongs isn’t quite as stormy as the disputes over where the wing goes, when to raise the gear, or how to lean — but there are still more than a few firm convictions out there. And although it may be openly acknowledged as anachronistic, let’s not forget that the tail-dragger configurations are still often referred to as “conventional gear” while the majority of us seem to be riding around in tricycles.

ON PREJUDICE…
Leaving out the relatively few aircraft having landing gear in a tandem configuration (two sets, one behind the other) where any “training wheels” might be of the outrigger variety, there are basically these two main types of aircraft. There are those with the third wheel out front, which tailwheel pilots might justifiably consider as a training wheel, and those having it in the back (in which case the new-to-tailwheel pilot is definitely in for some training). The “fact” is, even though many tailwheel aircraft are often quite Spartan in terms of creature comforts, not to mention operating costs, tailwheel pilots don’t need big watches. Just taxiing in with one is worth a Rolex or two.

…AND HISTORY
Back when tail-draggers really did drag their tails … because it was a skid rather than a wheel … it actually contributed to a more stable rollout. (Strictly speaking, the term “taildraggerreally only refers to those without a wheel in back — those having them being more properly referred to as “tailwheel” aircraft.) Between the wars, when men were men and calling a landing field a runway was being charitable, the few nose wheel airplanes were actually a greater liability because of the fact that they so often experienced catastrophic failures when that little wheel hit a rut or a rock and the whole thing curtsied forward and became a very expensive weed-whacker. (Propeller clearance is also generally greater for tailwheel aircraft, which is another asset on a rough surface … as is their ability to pivot in tight quarters.) Then of course, paved runways came along. After World War II, both the military and the airlines bought into tricycle gear airplanes (even during the war, with designs like the P-38 Lightning). There were fewer washouts, and at the same time there was a big improvement in safety. Among the first civilian tricycle gear airplanes during and after the war were the Ercoupe, the Bonanza, the Tri-Pacer, and of course, the Cessna 172 “Land-O-Matic“, which hit the market in the mid-fifties.

THOSE DANCIN’ FEET!
In case you cut ground school, the main reason for relocating the wheel forward was physics — it was not cheaper to put the wheel out front, nor is it lighter or more streamlined. Having the main gear behind the center of mass has a similar effect to putting feathers on the back of an arrow. With tailwheel aircraft, the CG is behind the main gear so during deceleration, it confers only instability. With most of the weight behind you as you touch down, it’s like pushing a shopping cart from the wrong end. The weight wants to swap ends every chance it gets; lateral excursions only amplify things, requiring deft jabs of rudder, differential braking, or power (which doesn’t usually help to slow you down at all) in order to get back on track. If you have ever piloted a boat of even moderate size, you may recall having to kind of lead your turns. That’s kind of what taxiing a tailwheel airplane is like. You have to perceive the need for the correction, make that correction … and then correct for your correction.

ON BEING GOOD
Well, not to sound euphemistic, but it encourages proficiency (not to mention attentiveness). Crosswind landings are obviously easier to screw up, but for those who fly tailwheel aircraft frequently and whose operating envelope is large, they can also allow more latitude. There are two reasons for this. One is that they generally have more rudder authority to help keep the fuselage going straight. Secondly, greater braking is possible without risking a wheelbarrow ride on the nose wheel (resulting, among other things, in the inefficacy of the brakes), and less control. It reminds me of Kennedy’s quip about having a Yale degree, versus a Harvard education: In a tailwheel aircraft, your feet get an education. So for that matter do your hands, when taxiing away from or across any appreciable wind (which in a Cub can mean five knots). You become a veritable stick and rudder convert.

ON BECOMING AIRBORNE…
Since a tailwheel airplane when taxiing is always in a climb attitude, they tend to fly off the ground sooner. If you think about it, in a tricycle gear airplane, the elevator must be up to raise the nose, which creates a greater tail-down force (opposing lift); however in a tailwheel airplane, the elevator must be down to raise the tail, which contributes a tail-up force (adding to the total lift). Also, since tailwheel airplanes usually need to be in a full stall attitude to make a three-point landing, they slow down and stop within a shorter distance.

…AND STAYING ON THE GROUND
Why do they need to make a three-point landing? Well, unless you deftly manage the somewhat confusingly named wheel landing (where one lands a tailwheel aircraft on the mains and then slowly lets the tail down), once the mains hit the ground, the back end of the airplane wants to do the same. This of course greatly increases the angle of attack, and up you go. In a tricycle gear airplane, the center of gravity is forward of the main gear. This makes the craft both directionally stable during deceleration and contributes toward keeping the nose down, because the forward pitch of the nose wheel making contact also serves to decrease the angle of attack of the wings.

WHY BEING GOOD MATTERS
Most tailwheel aircraft work for a living, often in less than optimum conditions, and are generally exposed to greater operational risks, and are generally older than their front wheel siblings. That said, a significantly smaller percentage of tailwheel aircraft accidents are pilot-related.

  • Yes, it is true that tailwheel aircraft suffer proportionally more takeoff accidents (roughly 50% more).
  • Yes, they average a much higher percentage of accidents during low-level maneuvering flight (nearly three times as many … probably mostly due to what I already said in the first sentence of this paragraph).
  • And yes, tailwheel airplanes have a much higher (by roughly half again) rate of mechanical or maintenance-related accidents (especially airframe and control system failures) than tricycle gear airplanes.

Yet it is actually the tricycle gear airplanes that have the greater proportion of pilot-related accidents, and believe it or not are also the ones with a worse record for landing accidents! Tricycle gear airplanes are actually the ones that…

  • are landed hard, long, or otherwise poorly, more often … which may have something to do with the fact that nearly all basic trainers have tricycle gear.
  • But tricycle gear airplanes also seem to suffer three times as many weather-related accidents (such as continued VFR into IMC, or scud running).
  • And guess who also runs out of gas the most? Yes. Try twice as often as their elder brothers (must be that attentiveness thing).

THE BOTTOM LINE: Generally, once you’ve run the tailwheel gantlet, it’s like going from a manual to an automatic transmission — landing a trike will seem like a cakewalk. All in all, aside from the challenge of improving one’s flying finesse, or the vicarious thrill of reliving a bygone era, tailwheel airplanes have the obvious advantage out in the boondocks. For that matter, such an advantage applies anywhere else there doesn’t happen to be a runway … should the need arise for an unplanned stop en route.