Light beam area for Landing Lights

[Dave Cogan]

I am currently using 2 x standard GU5.3 type 12 volt halogen lights (70 watts each) per wing.
This is 300 watts and I have to reduce the current by about 5 amps so I am thinking of replacing 1 x light from each wing with a 50 watt light.
I have been told I can get a better type of light in that size that draws 50 watts but gives the light of a 65 watt halogen.

My question!
You can get them with different spread of light. Fore example 16 deg, 36 deg and 60 deg.

Am I better with a narrow, concerntrated beam or a spread out beam?
I'm thinking the middle range might be best.
Any ideas?

[Kyle Boatright]

Most aircraft landing lights have 10-12 degrees of dispersion. If you widen that angle, the lights lose range. I think you'll be disappointed in anything other than the narrow beam.

For what it is worth, I recently installed a 30W HID landing light with a 36 degree dispersion angle. It has an effective range of maybe 150'. I'll be adding a second light with 12 degrees of dispersion to give my landing light set-up both good distance and good spread.

[lostpilot28]

Kyle, how can you tell what the angle is? I made 2 HID light brackets identical to the Duckworks brackets. Then I robbed the reflector from the $15 off-road lights I bought at Harbor Freight and mounted the HID lights inside them.

I have no idea what spread or distance I'll get from this setup. I mounted them in the last bay of each wing. The lights are 35W D2S type. I was hoping they would give me much more than 150', but your post has me worried.

[Kyle Boatright]

Originally Posted by lostpilot28

Kyle, how can you tell what the angle is? I made 2 HID light brackets identical to the Duckworks brackets. Then I robbed the reflector from the $15 off-road lights I bought at Harbor Freight and mounted the HID lights inside them.

I have no idea what spread or distance I'll get from this setup. I mounted them in the last bay of each wing. The lights are 35W D2S type. I was hoping they would give me much more than 150', but your post has me worried.

The lights I'm using are factory assembled with a reflector and lens. The dispersion angle is determined by these accessories. If you're looking for a narrow dispersion angle, you probably want something listed as a driving light, or a spot beam. If I recall correctly, fog lights and off-road lights tend to have wide beam angles.

[Ron Lee]

Why do you think that you have to reduce your current (amps) demand?

[mike109g6]

Originally Posted by Dave Cogan

I am currently using 2 x standard GU5.3 type 12 volt halogen lights (70 watts each) per wing.
This is 300 watts and I have to reduce the current by about 5 amps so I am thinking of replacing 1 x light from each wing with a 50 watt light.
I have been told I can get a better type of light in that size that draws 50 watts but gives the light of a 65 watt halogen.

My question!
You can get them with different spread of light. Fore example 16 deg, 36 deg and 60 deg.

Am I better with a narrow, concerntrated beam or a spread out beam?
I'm thinking the middle range might be best.
Any ideas?

Dave,
Why are you going with 4 lights total? Why not just 2 100W Halogens? One in each wing. Remember, it's not so much watts for your electrical system-except for wiring size- vs total amps used. ie, 100w=10amps is typical of halogen lights like my landing/taxi lights are. Check out Aeroelectic.com and you'll see what I mean. Many wiring diagrams and wire size chart available. HID lights are typically even less amps and more visible light, though more expensive.
Mike H 9A/8A wiring/instrument panel done-AT LAST!