Touch & Go's (article)
Aero-Tips 08.09.06
Here's one that's sure to generate some reader mail... and that's my hope, that it gets people thinking. Question for the day: are touch-and-go landings truly instructional, and are they worth the risk?
A training standard
Touch-and-goes, a landing with just enough time on the ground to reconfigure and take back off, are a rite of flight instruction. All too often, though, touch-and-goes result in loss of control and a runway excursion; "T&Gs" are a frequent contributing factor to inadvertent landing gear retraction on the runway and even seem to play a part in gear-up landings. Given that T&Gs appear so frequently in accident write-ups, why is it we still train the maneuver, and should we re-think the T&G maneuver?
Training benefit
There are two benefits of T&Gs:
Time. T&Gs provide more landing practice per hour. A student flying T&Gs might log seven or eight takeoffs and landings in an hour, while full-stops might permit only four or five.
Money. More landings per hour means less money for the same landing experience. Some airports (especially outside the US) encourage T&Gs by charging fees for each full-stop landing.
However, flying a T&G the pilot must, in a very short time...
Quickly and correctly manage power controls. In piston airplanes this may be up to four inputs: throttle, propeller, mixture and carburetor heat. If the pilot does not set mixture to rich before landing, or the airport is at a high density altitude, this may require attention at a time of rapid change. Turbine pilots may have to direct attention to engine indicators to avoid overtemps or overtorques.
Reconfigure the airplane, including flap and, if equipped, cowl flap position. Here's where the danger of accidentally pulling up the landing gear is manifested again and again in accident reports.
Retrim the airplane. Many aircraft are trimmed radically nose up, away from a safe takeoff trim position if the pilot uses trim for landing. Failure to reset the trim is known to have resulted in fatal post-crash stalls.
Maintain directional control throughout this very high-workload maneuver.
Review and evaluate the landing process if any training benefit is to be realized.
Are T&Gs worth it?
I contend that more valuable instruction comes from landing to a full stop, reconfiguring the airplane using the postlanding checklist, taxiing back to the runway threshold and making another takeoff. This provides "scenario-based training" that encompasses the entire landing sequence, reinforces the use of a pretakeoff checklist insure proper configuration before each flight, and gives the time to critique and discuss the individual landing so learning is not lost in a jumble of T&Gs reviewed as a group after the lesson is complete.
Note: T&G practice does teach the advanced student and certificated pilot a technique for an emergency go-around should he/she detect a runway hazard after touching down -- such as an animal or another airplane on the runway, or the inability to meet a "land and hold short" requirement. So T&Gs do have a limited training benefit as an emergency maneuver.
Aero-tip of the day: Ask yourself if you're really getting the full learning benefit of practice by doing touch-and-goes, and if the T&G maneuver is worth the known risks.