Citation Fall 2000

• Fuel Sump Drains
• Safe Flight Corporation Can Help Replace Your Current N1 Reminder
• Cold Weather Slush Boot
• Don’t Damage Your ACM
• Check Your Landing Lights

Fuel Sump Drains

Sumping fuel for your wings is an important step in keeping contamination out of your fuel cell. Repeated use of the sump can cause leakage. If your airplane has been built within the last 15 years, you probably have sumps that can be resealed without draining the tanks.

Instead of pushing up and turning the center portion of the sump, apply enough pressure on the center portion to allow rotation in the opposite direction. The center will pop downward and expose a blue or black o-ring. The sumps are made so that fuel will not leak much during this process. Remove and replace the o-ring with a new one (p/n MS29513-010). The center portion of the sump can now be reset flush.

Safe Flight Corporation Can Help Replace Your Current N1 Reminder

Safe Flight Corporation makes an electronic computer to replace your current N1 thumb wheel reminder. The computer has three different settings: one for climb, one for takeoff and one for cruise.

It also adjusts for anti-ice selection and has an OAT input for correct calculations. It is possible for it to be installed in the pilot’s panel with very little panel rework. Most installations can be done with a field approval or with a 337 form authorization.

Cold Weather Slush Boot

Cessna has offered a nose gear slush boot for winter operations for many years (p/n CJMD232-005). Installation procedures are in the maintenance manual and use Ty-raps to secure it to the strut. A common problem that technicians see is that the upper end of the boot does not stay on the nose gear. The gear is designed at the upper end without a “flange” or edge for the boot and Ty-rap to set it against. Try using a hose clamp p/n NAS1922-0275-1 instead of the Ty-rap at the upper end. The hose clamp will secure the boot tighter to the strut than a Ty-rap. The clamp must be positioned so that the nose gear scissors do not interfere with the clamp. Position the clamp on the outside of the boot instead of putting it through the small pocket on the boot.

A word of caution: Make sure that the strut is fully extended during the installation of the boot and clamp. If the strut is not fully extended and the boot is installed, it may cause the nose strut to not extend completely during takeoff and the nose gear to not go in the uplock hook correctly.

Don’t Damage Your ACM

On Cessna models S550, 560, 550 Unit 460 and on, Cessna has installed a Ground Bleed Air Pressure Switch. This switch is installed to shut the Ground Bleed Air Valve if advancing the right throttle for any reason.

During several pre-inspection ground runs, we have found this switch to be inoperative. If this switch is inoperative then the ACM can be over-pressurized and possible damage can occur to the ACM. A periodic functional check can verify operation and prevent possible damage to the system.

For more info, contact Joe Austin in BTL at 800.525.2376, or Ed Johnson in LNK at 800.228.4277.

Check Your Landing Lights

With winter weather approaching, we have fewer daylight hours and more evening hours. A quick check of your gear mounted landing light can be performed, without jacking the airplane.

With both landing lights selected “on,” stand directly in front of the landing light with your legs together and approximately four feet in front of the wing. Note the area on your legs where the light is concentrated. Go to the other side and check the other landing light. If the light beam does not hit your legs like the other side, an adjustment is suggested.

There is a procedure in the manual to adjust lights correctly, but using this quick check will help determine if adjustment is needed.

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