With the flying season almost upon us, what activities can be carried out, more than a thorough walk around, to ensure that the first flight after storage will be a safe one?
First of all make sure that the battery is in good condition and fully charged. It is not only the first start after a period of inactivity that may put a heavy demand upon the battery, but also it would be beneficial to have enough battery power to help with some additional engine cranking as we shall see later.
The best way to ensure battery charge is to remove the battery from the aircraft and use a slow "trickle" charger rather than a rapid charger. This has less risk of damaging the battery. Slow charging of the battery has more chance of recovering a discharged battery and also rapid charging of a battery can sometimes cause damage by delaminating the cell plates.
Next check the fuel for water. Condensation will form on the inside walls of a fuel tank and also on the fuel surface if the fuel temperature is below that of the dew point. This can cause some water to become suspended in the fuel as well as water to form in the bottom of the tank. What we need to think of when checking fuel drains is that as the temperature of fuel decreases, so does it's ability to hold water in suspension.
So the fuel will contain less water after being exposed to cold ambient temperatures - which tends to be overnight. It would also help if the aircraft has been stood still without any movement as agitation will encourage the mixing of water and fuel at the boundary where the two meet. The best time to check fuel drains is first thing in the morning before the aircraft is moved.
Next thing to turn our attention to is a full walk around. This should also include the condition of the brakes. It is possible that the brakes could be seized if the aircraft has been left unused for a period, so care should be taken to make sure that the brakes are free. This is especially important if the brakes are seized. It is best not to find out that the park brake is on in the cockpit, but the brakes are not actually on, after you have started the engine - this could be an expensive oversight.
During the walk around, remove all of the control locks, pitot and static blanks, and any engine blanks that you may have applied to exhaust, inlet etc. Once the blanks are removed, have a thorough check for any stowaways that you might have. Birds, animals and insects all find dormant aircraft a good place to make their home so have a good look in the engine bay, in accessible areas of the airframe and especially pitot and static vents.
If there is any evidence of insect debris in the pitot and static vents do not be tempted just to remove the visible blockage, think what may be happening inside. Some insects use these vents as homes and use the pipe runs as small breeding areas. So what you found as a blockage at the vent opening may only be an indication that there is a further obstruction of insect larvae further down the line.
If you find evidence of insect infestation at the vent opening, have an engineer check the whole line for obstructions. This is often not too complicated and it's better to find nothing on the ground than to be left in the air without pressure instruments.
Next have a look at the Perspex of the cockpit canopy. Has this developed any new surface marks over the winter period - scratches, abrasion marks or even surface damage from bird droppings? These surface marks can be removed by using specialised Perspex blending and polishing kits which can significantly improve visibility especially when flying into low sun, something that happens quite frequently in the early and late parts of the season.
Finally make sure that full and thorough pre flight run ups are completed. If the aircraft has been in extended storage and not run for some months, then gums and lacquers could have formed in the fuel system which could restrict fuel flow. So ensure that full power is available when doing the magneto checks and also check the throttle stop idle speed.
One final thing to pay attention to is variable pitch propellers. These are normally operated by engine oil pressure being fed to the propeller hub and, with the engine having had the oil changed, make sure that the propeller has full oil supply by cycling the pitch properly during the ground run.
Article sourced from AeroShell.