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Guess the distance

Cool photo, but I'd say it's extremely difficult to judge the distance. Sure, they look close, but the foreshortening effect of a long telephoto lens makes our intuition unreliable.

If someone could identify the aircraft types, it might be possible to get an idea by accurately measuring the difference between their real and apparent sizes...

Do you have a link to the original BBC news story?
 
Opening post: The lower one looks like a Boing 737, which is fairly small, as twin engined Jet liners come. Wing span is 34.3 meters. The upper one is amost certainly an Airbus A300-330, which is huge. It has a wing span of 60.3 meters.

Since they appear to be of equal size in the picture, the top one must be about twice as far from the camara as the bottom one. How far that is, is impossible to deduce from the picture without optics data, but from the hazing (note that the upper plane is definietely more hazy than the bottom one), I'd guess at least half a mile.

Hans
 
Here's a much more spectacular example:

http://www.airliners.net/open.file/652327/M/

Any British tabloid journo / editor worth his salt could get about twenty "flight of doom" stories out of that one.

That's a great photo. "Look, you can even see that the plane furthest from us is applying rudder in a desperate attempt to steer away from the collision!"

BTW every time I read your posts I start to feel hungry ;)
 
The top plane lloks like a 777 to me (I don't believe JAL operates Airbus aircraft out of LHR).

The lower plane looks like an Airbus to me because the rear of a 737 is slightly more truncated than that of an Airbus 31n.

It's a great photo though. The one in the paper I saw was even better, they were just about to "crash".
 
That's a great photo. "Look, you can even see that the plane furthest from us is applying rudder in a desperate attempt to steer away from the collision!"
Which would show more ignorance. You don't turn a plane by applying rudder (not alone, at least). A desparate applying of rudder at low altitude is a sure recipe for disaster.

Hans
 
The top plane lloks like a 777 to me (I don't believe JAL operates Airbus aircraft out of LHR).

The lower plane looks like an Airbus to me because the rear of a 737 is slightly more truncated than that of an Airbus 31n.

It's a great photo though. The one in the paper I saw was even better, they were just about to "crash".
The poster on the pilot forum linked to by crispy duck identifies the JAL aircraft as a Boeing 777-300 and the DHL as an A300.
 
Which would show more ignorance. You don't turn a plane by applying rudder (not alone, at least). A desparate applying of rudder at low altitude is a sure recipe for disaster.

You cannot steal my Pulitzer with inconvenient facts :mad:
 
I watch Formula One racing a lot, and the shots of the cars coming down the straights always look as if they are bumper to bumper (as if F1 cars had bumpers....hehe). As they turn so that the camera gets a passing shot, you can tell the actual distance between them.
And that's at distances much closer than these aircraft shots are taken.
 
A long lens can also make things look much closer together than they are. Do you think that a person taking pictures of airplanes flying by would have a telephoto lens?
 
As Hitchcock showed, these things are easily manipulated (dolly out, zoom in). Theoretically, if you have two planes a 10 kilometers apart, and a camera 1000 km away, and you could magnify enough to get a picture, the planes would appear to be nearly on top of each other. Looking at Crispy Duck's photo, if you know the height of the plane at the front and back, and you compare that to the apparent height in the photo, that would tell you how far away the camera was, and from that you could figure out the distance. Other than that, I don't think there's any way to figure it out.
 
If you venture into the Pprune thread that I linked to above, you'll find that some good detective work has been done already. The photograph was taken by a professional sports photographer covering a football match, at West Ham, I believe. One of the main holding areas for Heathrow is nearby. The photographer, of course, was using a huge lens. He spotted the aircraft (the game was quite dull, by all accounts), realised that their paths would cause their silhouettes to overlap, and grabbed the photo. No doubt he or his agency then hawked it round their usual gutter press clients as fodder for the standard "flight of doom" story, despite being fully aware of the foreshortening that the lens would have caused.

The BBC story, while attempting the appearance of balance, still leaves the impression that something must have gone wrong, despite the spokespersons denials (or perhaps I'm just reading too much between the lines). Their original story was let down by the claim at the end that normal seperation is two and a half miles - that's true, but only for horizontal separation. Normal vertical separation is 1000 feet, a fact which they've now added, without removing the earlier contradictory information.

Cynical, moi?
 

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