Home of N2471U

April 17, 2019 Replace Landing Light

The ubiquitous GE 4509 100w Landing Light needed to be replaced. The 4509 has a rated life span of 25 (!!) hours - not very long. Though we can’t be sure, we may have got good life out of the bulb - lasting longer than expected. But, still, 25 hours! Pathetic. It is worth the $12 price tag, but not worth our time to replace so often.

Fortunately, it is an easy drop-in upgrade to a LED bulb with thousands of hours expected. The new Whelen Parmetheus Plus P36P1L Landing Light should be a lifetime purchase. There is a PMA from the manufacture, so this type of replacement can be done by the owner in accordance with applicable FARs.

⚠️ Disclaimer: I am not a mechanic. Do at your own risk, do not blame me for some fault or injury! Seek help from your mechanic! ⚠️

Unboxing 1


Old, burnt out light 4

Front profile view 5

Unscrew the retainer housing on the build and gently remove 6 Remove retainer housing. Be nice to the old hardware! 7

Disconnect old wires.
:warning: Disconnect power source or test with a multimeter! :warning: 8

Close shot. 9

Be careful that you do not lose the terminal screws! 10

Old bulb 11

New bulb, pretty! 12

Connect existing wires. Instructions indicate which terminal is which. However, per the instructions the bulb will not work if polarity is reversed, nor will it be damaged. :+1: 13

Fit bulb into housing, honor the notches and it will seat in the existing space. Instructions indicate a drop in replacement, but I can see how some cowlings might require modifications. 14

Ops check! :sunglasses: 15

Wrap up installation, by screwing the retaining housing back in. 16

Post installation, double check. This is the light output in a lighted hangar. The top cowling is off for other work, it is not needed to take off for replacing the landing light. 17