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enter image description here

I'm assuming this is just a matter of available space but it seems you could get 4 across all aligned but maybe there is another reason. The image is from McGuire AFB but I've seen this on other AFBs.

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    $\begingroup$ It's for good luck! (Just kidding.) Aren't the 45° spots closer to the taxiway and would be for confining the wings, as you've noted, for available space? Perhaps there's more to it, can you show us other examples? Thanks. $\endgroup$ – ymb1 Dec 10 '19 at 22:47
  • $\begingroup$ I see it at Beale AFB, Tinker AFB, March AFB and Albuquerque Airport. There seems to be a lot of various layouts for fighters and tankers/cargo. Some are all aligned while some are all at 45s, but there are a few mixed and I'm just not sure why. $\endgroup$ – William Taft Dec 10 '19 at 23:18
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    $\begingroup$ Because that's how the lines are drawn on the ground. $\endgroup$ – Mast Dec 11 '19 at 13:04
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    $\begingroup$ To protect them from Japanese saboteurs. $\endgroup$ – Harper - Reinstate Monica Dec 11 '19 at 17:25
  • $\begingroup$ Look at the spacing of the planes. The angled ones are closer to their neighbors. But if you did them all that way you wouldn't be able to get them as close. $\endgroup$ – Hot Licks Dec 12 '19 at 3:25
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The main example in the question body is to confine the wing from the main taxiway, which runs across the bottom of the image.

It may not seem like it, but a 50 m (164 ft) wide plane like those tankers parked at a 45-degree angle saves ~15 m (approx. one-third of its wingspan).

The reference used by the USAF is AFMAN 32-1084 (PDF), from which:

2.1.5.4.1. Parking Dimensions. Table 2.9 presents the minimum geometric criteria for fixed-wing apron design. When designing new aprons for AMC bases hosting C- 5, C-17, KC-10, and KC-135 aircraft, provide 15.3 m (50 ft) of wingtip separation.
EXCEPTION: When you are rehabilitating an existing apron, provide the maximum wingtip separation the existing apron size allows (up to 15.3 m [50 ft] but not less than 7.7 m [25 ft]). This additional separation is both desirable and permitted.

By measuring on Google Earth, the angled spots are a perfect fit for the very large C-5 Galaxy, which has a wingspan of 67.89 m; halve that and add the 15.3 m clearance from the taxiway to check. A non-angled C-5 would violate that. (The measurement I made in the image below shows two half-span C-5s plus the clearance, with superimposed C-5s via pinterest.com.)

enter image description here

Being an AMC base, it's very likely those spots were made for the C-5 for whenever it visits.


For the other examples you've stated in a comment (Beale AFB, Tinker AFB, March AFB and Albuquerque Airport) in the same order:

enter image description here
The bottom row is between two taxiways, so it's the same reason as the main example. It also makes parking and taxiing out easier.

enter image description here
Those by the hangar are for ease of taxiing out instead of a hard left and potential for collision.

enter image description here
Plenty of space. I couldn't find a 45-degree parking.

enter image description here
Same as Beale AFB.


(All imagery is via Google Earth)

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  • $\begingroup$ Thanks for the info. I was also looking at Barksdale AFB, and in the google maps view there are 5 "rows" of B-52s, but only one of the rows has a plane at 45 degrees by the taxi line while 3 of the others do not. For Tinker AFB, the apron on the west side has the weird layout. For March, there is a C17 at a non-45 on the south side, but still at a weird angle compared to the others. $\endgroup$ – William Taft Dec 11 '19 at 13:24
  • $\begingroup$ @WilliamTaft: For Barksdale, I checked the historic imagery, and from Oct 2016 for example, the same B-52 location is used normally in line with the painted markings. Perhaps the current imagery the plane was being moved, or not yet moved into the final position. As for the March C-17, the apron is narrower there, and all the adjacent spots are also tilted, so it's for the same reason (making space). $\endgroup$ – ymb1 Dec 11 '19 at 13:45
  • $\begingroup$ Likewise for Tinker, because of the weird layout of the apron itself. Planes kept getting bigger, so they had to adapt the apron to make the best use of the available space. $\endgroup$ – ymb1 Dec 11 '19 at 13:54
  • $\begingroup$ If you look at the OPs image from McGuire, there appears to be plenty of wing-tip room to rotate the planes from 315° to 270°. However, for those planes that are parked at 315°, they would have a much sharper turn to make it to the 90° direction on taxi-out if they were parked facing 270° and that may not be a turn they'd be able to make. I do agree with your assessment of the images you posted, though. $\endgroup$ – FreeMan Dec 11 '19 at 18:43
  • $\begingroup$ @FreeMan: see now ;) $\endgroup$ – ymb1 Dec 11 '19 at 23:51

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