General Information Daily Inspection Tug Equipment Start from Cold Start in Hot Weather Engine Ground Run Taxiing Hangaring Cleaning
- In order to avoid damaging the flaps, the flaps should always be down when parked or hangared to facilitate entering or leaving the aircraft. Also when anyone approaches the aircraft lower the flaps to permit access.
- The electric fuel pump should be ON whenever the engine is running (the exception to this being during the power checks).
- The anti-collision light should be ON whenever the engine is running.
- Ensure articles in the aircraft are strapped down. The wide expanse of perspex is particularly vulnerable to loose objects. Spare tow rope should be on floor behind pilot seat. Passenger side straps should be connected and tightened.
- A cylinder head temperature gauge is fitted to all aircraft. Some give the option to switch between cylinders – in this case cylinder 4 should be selected.
- The DR400s have hours meters which should be used for recording hours instead of the tachometer.
- DR300 canopy consists of two gull wing doors with an awkward latching lever. Care is needed to ensure the locking pins are located correctly. There is a bottom pin beside the door latch and another at the top of the canopy at the innermost corner. To close the canopy, ensure both pins are engaged and then close the locking lever ensuring it engages the lugs at the back of each of the doors.
Pilots must complete a daily inspection and this must be recorded in the Tech. Log before flying commences.
In addition, special attention should be given to the following items:
- Oil level should be kept between 6.5 and 7.5 quarts. Aim to add enough to give 7 quarts. Filling jugs and paper towels are to hand.
- Nose wheel leg – inspect for cracking, particularly at the attachment brackets. This is important in view of the rough nature of the airfield. Also, check the nut and bolt on the rear of torque link is secure.
- Condition of the main landing gear – remaining oleo travel must be 2.75 inches or more. The top of the wheel fairing must be below the check hole in the fixed fairing when the aircraft is empty.
- Silencer – check that there are no holes and that the silencer is secure.
- Air filter – not obstructed by debris, particularly grass seed or insects.
- Condition and security of the propeller and spinner.
- Tow rope release – check for correct operation and test under tension.
- If accessible check the cylinder heads. Look specifically for any cracks on each cylinder head. The most likely area is between the exhaust port and the spark plug hole on the lower side of the cylinder, but there are instances of cracks developing from small areas of corrosion between the base of the cooling fins. Cracks maybe masked by general discolouration due to dirt, heat and/or paint flaking.
- Condition of the tow rope and its weak links must also be checked. See the ‘Ropes’ page for more information.
The standard issue of removable equipment for each tug is:
- 2 ropes – 1 in use and 1 stored in the tug (In the footwell of the rear seats)
- 1 headset
- 1 clipboard for tug log cards and a pen
- 1 hand fire extinguisher
- The Tech. Log and airspace maps
- 1 Personal Locator Beacon (PLB)
Start from Cold
Ensure the aircraft is parked on the grass, clear of stones and debris (including the ‘bare’ patches of grass near to the pumps which you may have to taxi over). The aircraft should not be started where the slipstream would affect other aircraft or gliders or where debris could be blown over aircraft, gliders or buildings.
To start: Use the ‘Scan’ method and include the following;
|Prime Cylinders||2 to 4 pumps of the throttle. If engine is warm then a single pump|
|Throttle||SET, just off idle|
|When engine starts;|
Note: CA starts on the ignition key. The right magneto is automatically isolated for start up.
|Starter Warning Light||Check OUT|
|Throttle||SET 1000-1100 rpm|
|Oil Pressure||GREEN BAND|
|Alternator||ON, check charging|
Note: It may be necessary to use a higher rpm for the engine to run smoothly particularly if ice has formed during cranking. Reduce to 1000 rpm when smooth.
Switch the electric fuel pump OFF to check serviceability of the engine driven pump, this should be done whilst taxiing to the launch point or whilst carrying out the power check. It should be ON for normal operations.
Caution: Carb heat bypasses the air filter and so should not be used whilst taxiing. It may be needed soon after start, if carb icing is likely.
Start in Hot Weather
The above starting procedure may not be suitable in hot weather. A long period of cranking and too much priming before engine start are causing excessive stresses and premature failing of the starter motor and exhaust systems. Backfiring and high RPM are signs of incorrect technique being used.
In hot weather consider the following:
- First start priming – three pumps only
- Throttle setting – Take care to set the throttle so that when the engine fires it does not exceed 1100rpm
- Hot or subsequent starts – mixture lean until the engine fires and then to rich. Start on both mags in these circumstances.
Engine Ground Run
The time at which you do the ground run should be considered carefully. It should occur within a few minutes of flying. If you taxi out to the West run or North East run in anticipation of launching, it is very tempting to do the ground run when you get there, fine if you immediately start towing. If it looks like a wait of more than 10 minutes, you should shut down until needed. After start re-warm the engine, then do the ground run up (as shown below) and then the flight, at a pace to prepare the engine for full power. Taking off with a cold engine is a sure way to damage it. For SW run operations, don’t leave the parking area until you can see a need arising, then allow sufficient time to taxi across, warm the engine, carry out the ground run up and then start flying, this will avoid the need for an unnecessary shutdown.
After the engine has reached a reasonable temperature, the ground run up should be completed as follows:
|Position||Suitable for engine run and clear behind|
|Carb Heat||ON, check for a positive drop|
|Carb Heat||OFF, check for recovery to 1800 rpm|
|Right Magneto||OFF, check for max drop of 125 rpm|
|Left Magneto||OFF, check for max drop of 125 rpm|
|Magnetos||BOTH, check max drop difference < 35 rpm|
|Throttle||Slowly to IDLE, check 800 +/- 50 rpm|
Before first flight, IDLE rpm may be lower, in which case if engine is running normally, check again after completing the first flight.
After the run up, reset to ground idling at 1000 rpm. Providing that the engine is responding smoothly, there is no minimum oil temperature required before take-off.
Our airfield is generally rough, so taxi slowly.
With the nose wheel steering mechanism engaged, rudder pedal movement will then turn the nose wheel, further rudder pedal deflection will cause the wheel brake on that side to actuate. Whenever possible, try and taxi in such a way that you don’t need the brakes to operate. The same technique applies to CB except the brakes are toe actuated. If the steering mechanism is not engaged nose wheel steering is not available. To re-engage the steering, stop the aircraft, apply a little power with the stick forward which will cause the aircraft to nod forward and engage the mechanism. Very tight turns should be avoided as this is detrimental to the nose wheel steering mechanism.
The aircraft has a tendency to nod when taxiing over rutted ground, particularly hanger ridge. Taxi slowly and cross the ruts at 45 degrees. Also pay attention to your route to prevent the nose wheel from entering any significant dips or depressions. This will reduce the risk of tip contact.
Choose your route carefully and use only the smoothest areas of the airfield – standard routes can be viewed on the ‘Launch Points’ pages.
It is the tug pilot’s responsibility to refuel their aircraft if the fuel tanks are indicating less than a quarter full and at the end of the day’s flying.
The tug should be stopped short of the perimeter track near to the fuel pumps, with the tug mover used to manoeuvre the aircraft over the road, stopping short of the fuel pumps. Ensure the electrics are off and connect the earthing strap to a metal part of the aircraft. Fill the tank to full – the only exception to this may be prior to launching a competition grid, before setting out on an aero-tow retrieve or before maintenance (NB; the auxiliary tank on CB and YM are normally left empty).
After refuelling, stow the fuel pipe and earthing wire and record the uplift in the fuel record shed.
Once fuelling is complete, return the aircraft to ‘air side’ or to the hangar.
More information can be found on the ‘Fuel‘ page.
Always put the Robin in the hangar tail first. Ensure that it comes out nose first. If it comes out tail first the tail skid can hit the tarmac and could fold back or break! When in the hangar ensure the Tech. Log has been completed and the canopy is closed.
Cleaning equipment is available in the tug hangar. Tugs should be cleaned of mud and bugs after flying. Canopies and propellers should be clean before flying.