What is the source for this distance? Anecdotal evidence suggests identification at much more than 1 1/4 miles with much less than a planform angle. Of course, knowing what the bad guys are flying helps identify things early, and there is also real and anecdotal evidence of pilots mis-identifying planes within gun range. I've never seen anything definitive and it's always an interesting discussion on this topic!
Regards,
Hammer
Well, the source is me. About 10 years ago I was interested in how close Warbirds was to reality and what changes to the icon system would better reflect reality.
I freely admit there are limitations to computers when it comes to visual simulation but I also believe there is a better compromise between no icons and the rather silly icon system we have now.
As for how I arrived at my numbers....
It was a multipart experiment, one I continue to this day in small ways but here is what I did 10 years ago.
I gathered all of the actual dimensions of the aircraft in game and I compared those dimensions to aircraft commonly flying today for the real world experiment portion. I found common modern airplanes that were similar in size to each game model.
I spent time at local airports playing a game trying to identify aircraft over known distances from my vantage point and comparing my guess to reality when the plane was close enough for positive identification (I have a long background in aviation and can recognize just about anything flying)
Conclusion one.......There is a big difference between I see an airplane and I see a Beechcraft Baron.
Conclusion two.......Knowledge of aircraft is critical. Aircraft I could identify at 2 miles my wife (who has spent a considerable amount of time around airplanes) had to look at the nameplate when it was parked.
I even enlisted air traffic controllers and other pilots in the experiment. I continue this silliness to this day. I am always comparing TCAS range in the Challenger with what I see outside the window. It is amazing how hard it is to spot a airliner sized airplane when you know exactly where to look and how close it has to be before you know exactly what it is. Just yesterday I played this game while tooling around in a 172.
The second part was to print scaled silhouettes of every plane in the game. I then gave the scaled silhouettes to my wife (and a few others ) for five minutes of study.
I measured scale distances and starting from scale 5 miles had the wife try to ID each type. I had her come in a half mile at a time and recorded the result. I did the same thing. I was able to correctly identify the aircraft much further out than she was until she became familiar. Then the distances got closer together but it was clear that outside of certain scale distances one could only determine basic characteristics and not enough to positively identify the aircraft.
109's look like P51's. Ki84's look like Zekes. 110's look like P38's from far enough away. Big planes were easy. Small planes were hard. Everything you would expect.
The 6000 feet for a 109 sized airplane comes from an average of part one and part two results.
The last thing I did was paint a white letter (it was an M so I could turn it upside down and make it a W) on a black background. The letter was the same size as the Tail ID on a B17.
The letter was reliably identifiable at 1100 feet by people with 20/20 or better (I have 20/10 20/15)
The specific number isn't incredibly important. The biggest issue is that a smaller plane should not be positively identified at the same distance as the biggest plane. A 109 is much harder to see and identify than a B24.
Anecdotal evidence is particularly unreliable because people have no distance reference unless they specifically are measuring something like this.
For example, if you are looking at an airplane flying directly overhead in the traffic pattern at the local airport it is 1000 feet away if its a piston engine plane. That is very close. Way inside guns range in the game.
And like I said earlier....there is a big difference between seeing a plane clearly and actually identifying it.