A question for our ATS pilots

Hey guys I have a question that I cannot find anything about online and hoped one of our pilots might be able to answer. I was coming home from work yesterday and saw a larger gulfstream-type aircraft on its final approach to MCO. It was heading south and I was heading north about 2 miles outside of the runway. It's landing gear were down and its taxi lights on all 3 struts were on and pulsating in unison. I used to work ground crew for air cargo and have never seen a plane pulse its taxi lights on approach. Is this some sort of signal to the airport or something?

When an aircraft is trying to be noticed or acknowledge a transmission, they may flash lights. It may be a radio failure, or a tower operator having trouble seeing the aircraft.

reply to post by djvexd


The pulsing landing lights is an option that some think increases visibility to ground observers and other air traffic.

Southwest Airlines had a few older B737-200s that flashed the landing lights alternately, not simultaneously.

I think it's more of a maintenance headache, and thus a cost issue today (at least for the Airlines) as it is hard on the light filaments.

Obviously, though, some Bizjets are still around that use them. I think I remember seeing it on Falcons, mostly.

Excellent....thank you both for your replies. I remember they used to flash lights at me when they acknowledged my tarmac guidance but, never seen it in the air before.

reply to post by djvexd


Yes, the taxi light flash, on the ground, serves as acknowledging the 'salute' from ground staff when clear to taxi. Usually the pilot signals by hand in daylight, and with the nosewheel light at night.

All aircraft have strobe lights to attract attention in poor visability. I confess that I have never heard of undercarriage lights strobed like that, but it's perfectly feasible to do so.

I know cop cars in my country have headlights strobed in addition to their roof lights

Like this?



Only on a biz jet?

[edit on 26/5/2009 by C0bzz]

actually it was the taxi lights located on the landing gear struts and the lights( all 3) were pulsing in unison.

reply to post by djvexd


Well, as I've said...depends on the airplane, where the landing lights are mounted.

Taxi light generally on the nose gear strut, in larger airplanes (not on a Cessna, though, for instance). You saw a Bizjet with the landing lights mounted on the main gear. Reasonable place for Landing Lights, since the gear is generally down for take-offs and landings (!)

The alternate flashing mode is likely disabled on the ground -- very distracting otherwise. ALSO, at night, they would be equally distracting during landings...so there is likely a switchable position, steady vs/flashing.

On commercial jets we turn on all outside lights (except the taxi light, of course) below 18,000 feet as common practice for improved visibility. Since Boeings and Airbuses don't have a variety of different lighting schemes. The former McDonnel/Douglas MD80/DC9 series have motorized landing lights that retract and extend out in the wingtips. The B737 series have landing lights that are motorized to extend, they are mounted on the flap jackscrew fairing "canoes", just outboard the engines.

There are also various Runway turn-off lights (similar to the cornering lights on your cars) and the wing lights, to look for ice at night.....

No need for me to chime in, Cap Weedwhacker has covered it all!!!!!