Aerotowing Procedure – PA18 Super Cub

CLIMB

Maintain requested tow speed as indicated on towcard, especially important with high performance sailplanes with water ballast (see towcard). If tow speed is left blank, use the following rule of thumb:

- Do not use steep angles of bank, be especially careful with new glider pilots
- Use full throttle and full rich mixture for proper cylinder head cooling.
- Be cognizant of the tow plane's noise footprint and use noise abatement flight paths
- Tow upwind if wind is strong
- Look for traffic, anticipate what's ahead, tow plane/sailplane combo is not too maneuverable
- If glider does not release at altitude specified on towcard continue to climb. If glider is still on tow far above specified release altitude, glider pilot might have lost sight of airport (especially a new glider pilot), so fly back toward airport.
- If divebrakes open on the glider, waggle rudder to inform the glider pilot. If divebrakes remain open, continue climbing near airport until glider releases. DO NOT release a glider with open divebrakes UNLESS there are obstacles ahead that the tow plane cannot clear. The 180 HP Super Cub and the Pawnees will climb towing a Blanik with divebrakes full open.
- If tow plane is approaching cloud base, wave off glider to avoid flying into cloud or having to reduce power significantly and shock cooling engine. If glider has not released, maintain tow speed and throttle back to stop climb and achieve level flight.

BOXING THE WAKE
- Boxing the wake is a normal glider training maneuver. Expect it occur without prearrangement.
- Glider will usually (but not always) descend first, indicating they will box wake. Pick a reference to fly straight ahead by, but if you need to turn during boxing the wake, use shallow bank angle

RELEASE
- After glider releases, tow plane turns left or straight ahead if left turn is not possible
- Make sure glider has released before turning and descending, sometimes hard to determine if glider releases on slack line

DESCENT & ENGINE ENGINE COOLING PROCEDURE

1. Use engine cooling procedure outlined in BESC Tow Pilot Manual (repeated here for Super Cub)
_a. At the time of glider release note cylinder head temperature (CHT)
_b. Reduce power to 2100-2200 RPM
_c. Do not exceed 85 MPH
_d. When CHT cools down by 40 - 50 deg F, smoothly reduce power to 2000 RPM and gradually increase speed to 90 - 95 MPH.
_e. Continue to reduce power smoothly in 100 RPM steps to no lower than 1600 RPM until reaching the pattern

2. Side slipping during descent and cool down not recommended due to uneven cylinder head cooling

3. For descent, the use of flaps is not recommended for the Super Cub (flap placard speed is 85 MPH for Super Cub)

4. Use clearing turns often during descent to avoid descending on top of another aircraft (especially important in the Pawnee, where downward visibility is impaired by wing

5. Do not fly too closely to other aircraft with the towrope attached

6. Use sink or steep turns to hasten descent

PATTERN & LANDING

- Enter on a crosswind or 45 degree entry leg. Space yourself into traffic flow. Watch for closed traffic on the crosswind when descending. Watch for ultralights when on crosswind and downwind legs when landing to the North, and on downwind and base legs when landing to the South.
- At AWO land on grass when landing to the North. Cross road between 350' MSL and 400' MSL to avoid snagging cars or people on the road. If you must land on the pavement to the North (Runway 34), be aware of the elevated approach lights on the extended runway centerline that start South of the road and run North leading to the runway threshold, and make a high approach accordingly.
- At AWO land on pavement when landing to the South. Fly a sidestep approach to avoid dragging towrope through Localizer antennas. Straighten out on centerline and do not damage lights at end of the runway on either side of the centerline.
- If you have to go around, consider dropping rope to avoid dragging it across anything on the go-around (like parked tow planes when landing to the North). ALWAYS be aware of when the towrope is attached to your tow plane.
- After landing and shutting down, move tow rope off of taxiway.

EMERGENCIES

- Be able to switch fuel tanks by feel and verify by looking
- Be able to locate the release handle by feel
- Don't hesitate to release glider if you or the tow plane is in imminent danger. Better to save the tow pilot and the tow plane than to lose the combination. Having said that, do not release a glider without a very good reason, especially at low altitude. This can be a tough call.
- Be especially vigilant for low altitude emergencies where there is not sufficient altitude and time to recover from an upset. An example of this is where the glider gets high during the initial climb and pulls the tail of the tow plane up, pitching the tow plane toward the ground. See page 12 for a Soaring Magazine article discussing this type of accident.
- If tow is aborted on the runway, release the glider and move to the left.
- If both the glider and tow plane cannot release, the success of landing while on tow is largely depedent on the tow pilot and the rate of descent that is used. Pick a long runway, fly to another airport if necessary. Set up a rate of descent of between 200 and 300 feet per minute. Higher rates of descent will be too high for the glider to match. Fly a slightly wider pattern and do not chop power and dive for the runway. Fly a stabilized approach to touchdown. After touchdown, do not decelerate to quickly and move to left to allow glider room.

Tony Smallwood/dec'04