AviRaider
Topic Author
Posts: 178
Joined: Thu Nov 01, 2007 10:07 pm

Intermittent Flashing Red Beacon On Aircraft

Thu Oct 18, 2012 2:26 pm

http://www.youtube.com/watch?feature=player_embedded&v=x-owRtLop08

So I was watching the video of American's newest 777-3 and I noticed that the flashing red beacon flashed intermittently and it didn't seem to have a pattern to it. I know there are all kinds of different types but specifically to the flashing kind, why is there no need for a consistent flashing of this beacon? Is there a reason that different aircraft have different flash patterns? I would think in this day and age studies would have weeded out the best beacon light types for safety.

Your thoughts?
 
vikkyvik
Posts: 11909
Joined: Thu Jul 31, 2003 1:58 pm

RE: Intermittent Flashing Red Beacon On Aircraft

Thu Oct 18, 2012 2:35 pm

Quoting AviRaider (Thread starter):
Your thoughts?

Looks like the frame rate of the video simply doesn't pick up a lot of the flashes.

They do flash at regular intervals.
I'm watching Jeopardy. The category is worst Madonna songs. "This one from 1987 is terrible".
 
rfields5421
Posts: 5712
Joined: Thu Jul 19, 2007 12:45 am

RE: Intermittent Flashing Red Beacon On Aircraft

Thu Oct 18, 2012 3:00 pm

The way electronic movie cameras capture images is very different than the way film captures images.

A film camper has a shutter - on a wheel for movie cameras.

When the shutter is open, all the light is available to expose the film.

With an electronic movie camera - the 'shutter' is open all the time, and the CCD is excited by the light. The camera reads scans of the CCD in a progressive order.

This makes some strange effects for fast moving objects like airplane props, and can also make lights which blink in a set pattern look intermittent.

See the prop on this aircraft - http://www.youtube.com/watch?v=6MpkvK2P2RM&feature=share

The same scan pattern issues cause the inconsistency you see in the video.
 
Goldenshield
Posts: 5015
Joined: Sun Jan 14, 2001 3:45 pm

RE: Intermittent Flashing Red Beacon On Aircraft

Thu Oct 18, 2012 3:10 pm

Quoting rfields5421 (Reply 2):
With an electronic movie camera - the 'shutter' is open all the time, and the CCD is excited by the light. The camera reads scans of the CCD in a progressive order.

This makes some strange effects for fast moving objects like airplane props, and can also make lights which blink in a set pattern look intermittent.

This is why I when I use my camcorder, I love using 30 FPS progressive setting. Not only does it completely get rid of these flaws, but it delivers that old school film feel.
Two all beef patties, special sauce, lettuce, cheese, pickles, onions on a sesame seed bun.
 
AviRaider
Topic Author
Posts: 178
Joined: Thu Nov 01, 2007 10:07 pm

RE: Intermittent Flashing Red Beacon On Aircraft

Thu Oct 18, 2012 3:18 pm

Well that certainly all makes sense. I didn't think about it from the filming device's perspective. Thanks all.
 
JAGflyer
Posts: 3453
Joined: Tue Aug 10, 2004 5:31 am

RE: Intermittent Flashing Red Beacon On Aircraft

Sun Oct 21, 2012 1:02 am

The red flashing beacon on the top of the aircraft as well on the bottom is called the "anti collision" light.
Support the beer and soda can industry, your recycle old airplanes!
 
User avatar
DarkSnowyNight
Posts: 1816
Joined: Sun Jan 01, 2012 7:59 pm

RE: Intermittent Flashing Red Beacon On Aircraft

Sun Oct 21, 2012 12:15 pm

Interesting.

Anyone else notice that the UA 787 in the background is flashing with regular interval consistency? Do these CCD issues only apply at certain frequencies?
Be A Perfectionst, You're Nothing If You're Just Another; Something Material, This Isn't Personal...
 
yeelep
Posts: 730
Joined: Mon Apr 04, 2011 7:53 pm

RE: Intermittent Flashing Red Beacon On Aircraft

Sun Oct 21, 2012 3:13 pm

The 787 anti collision light may be consistently visible due to differences between the LED design on the 787, as opposed to a xenon flashtube design.
 
flood
Posts: 1045
Joined: Sat Feb 14, 2009 7:05 pm

RE: Intermittent Flashing Red Beacon On Aircraft

Sun Oct 21, 2012 4:22 pm

The strobes on the 777 illuminate for a fraction of a second. If you're recording video at 30 frames per second and with a shutter speed of 1/60 for example (which is generally suited for 29.97 / 30 FPS), your shutter is only open half the time. That said, if the strobe happens to flash during a period when the shutter is closed, it's not captured by the camera.

The 787's LED "strobes" stay illuminated much longer, greatly increasing the likelihood of them being captured at such shutter speeds.
 
Okie
Posts: 3610
Joined: Wed Jul 16, 2003 11:30 am

RE: Intermittent Flashing Red Beacon On Aircraft

Tue Oct 23, 2012 2:35 am

Quoting flood (Reply 8):
If you're recording video at 30 frames per second and with a shutter speed of 1/60 for example (which is generally suited for 29.97 / 30 FPS), your shutter is only open half the time. That said, if the strobe happens to flash during a period when the shutter is closed, it's not captured by the camera.

Some of the early LED's that were adapted to AC circuits (for life expectancy) used half wave rectification. It was possible to record and never see the bulb illuminate on video depending on your timing to when you pushed the record button and frames per second. The human eye would always see it illuminated but it was really not illuminated half the time.

Okie

Who is online

Users browsing this forum: BlueLine and 11 guests

Popular Searches On Airliners.net

Top Photos of Last:   24 Hours  •  48 Hours  •  7 Days  •  30 Days  •  180 Days  •  365 Days  •  All Time

Military Aircraft Every type from fighters to helicopters from air forces around the globe

Classic Airliners Props and jets from the good old days

Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos