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Yesterday afternoon I photographed a Boeing 777-300ER flying over my home, according to radar data it was at approximately 32,000 ft. In the photograph there is another aircraft present, it is much smaller and higher in altitude (40,000-50,000 ft) and it is a small aircraft, possibly a drone or military. It did not appear on any flight tracking sites. I usually see military traffic flying in that particular route and heading. I have numerous "raw" images of this particular aircraft.

enter image description here

I originally though it may be an L-39 although that particular aircraft does not have a T tail design and I think that it would struggle at that altitude. The photographs were taken at 1545 EST over the LVZ VOR.

The aircraft was flying an almost perfect east to west heading usually reserved for military traffic. One interesting note is that it was not leaving a contrail. I routinely photograph B-52's, tankers, and fighter aircraft transitioning over my home at or about that altitude and they almost always leave contrails.

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    $\begingroup$ welcome to aviation.SE. If you want help identifying an aircraft, you will have to provide your data here in the open, we don't do anything via other means. $\endgroup$
    – Federico
    Mar 18, 2019 at 11:15
  • $\begingroup$ Also note that after enlarging it appears to be a single "inline jet" engine configuration similar to a U-2's fuselage? Thanks Joseph $\endgroup$
    – user38075
    Mar 18, 2019 at 11:15
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    $\begingroup$ I asked a co-worker who flew U-2 and he says that to his knowledge all the wings used have a taper on the rear. But he has not flown ALL the variants. Also he points out that there are no visible pods for sensors, which is common with operational flights. Plus the paint schemes on all the U-2 that he has seen as operational are low reflectivity paints, and would not appear as in the photo. How about giving us more data on your photo acquisition details? $\endgroup$
    – mongo
    Mar 18, 2019 at 12:52
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    $\begingroup$ as you seem to have created 2 accounts, please have a look on how to merge them and regain control over the question: aviation.stackexchange.com/help/merging-accounts $\endgroup$
    – Federico
    Mar 18, 2019 at 13:39
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    $\begingroup$ please use the edit functionality, if you want to add information. $\endgroup$
    – Federico
    Mar 18, 2019 at 14:47

2 Answers 2

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Using the location you gave, I tracked back aircraft in that area at that time, and found a scenario that fits with your photo:

777-ER from ANA and the jet in question
(Source: Flightradar24)

So, judging by that, the jet in question is actually a Learjet 31, as said by John K.

enter image description here

Here are some blueprints, and the dimensions are similar:

enter image description here

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    $\begingroup$ Wow well done!! $\endgroup$
    – John K
    Mar 18, 2019 at 17:48
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    $\begingroup$ I did a bit of pixel measuring. In the image, the Boeing 777-300ER is 87 pixels long; the Learjet is about 12 pixels long. A 777-300ER in 75 m long; a Learjet 31A is 15 m long. Putting all of these numbers together, we can infer that the Learjet was roughly 1.5 times farther from the camera than the Boeing. That's not too far off from the reported altitudes of 32,000 and 45,000 feet, particularly if the OP was at a higher elevation. $\endgroup$ Mar 18, 2019 at 19:40
  • $\begingroup$ any idea why the plane didn't leave a trail? $\endgroup$
    – Manuki
    Mar 19, 2019 at 14:56
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    $\begingroup$ @Manuki Contrails require specific atmospheric conditions that may be present at one altitude but not another. $\endgroup$
    – ceejayoz
    Mar 19, 2019 at 15:06
  • $\begingroup$ (I should note that my pixel values above applied to the size of the original image on my screen. The image has since been changed, and I apparently wasn't viewing it at the highest possible resolution. But the basic logic still holds.) $\endgroup$ Mar 19, 2019 at 18:46
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I'd say it's a corporate jet. Corporate jets normally play between 40-55000 ft, above the bulk of the airline traffic down in the 30s, so this is a perfectly normal sight.

Based on the wing planform with straight trailing edge and swept leading edge, and what looks like a T tail and ventral fins, I'm going with Lear 45 or a similar Lear variant (Service ceiling 51000 ft). The viewing aspect doesn't look like from directly below so the engines won't stick out very clearly. Lear 45

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    $\begingroup$ And, if you look carefully at the OP's photo, you can actually see a hint of something just behind the wings, in exactly the right place for the engines on a Learjet. $\endgroup$
    – Vikki
    Mar 19, 2019 at 3:16
  • $\begingroup$ What is the reason for this separation of flight levels? $\endgroup$
    – koalo
    Mar 19, 2019 at 14:41
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    $\begingroup$ Corporate airplanes just tend to have higher service ceilings, in the 50k range, while most airliners are in the low 40ish range, and generally operate between 30 and 40. It's unusual to operate right at your service ceiling - you have no surplus energy margin to speak of and it can take forever to get there - unless you are unusually light. You have to monitor your speed very carefully. If you slow down too much you have no choice but to descend. $\endgroup$
    – John K
    Mar 19, 2019 at 18:38
  • $\begingroup$ @JohnK: IIRC, the most fuel-efficient altitude is around the tropopause, so higher than ~36k isn't better. Just because corporate jets can fly higher doesn't fully explain why they routinely do. But since they can while airliners can't, corporate jets fly higher to stay out of the way? $\endgroup$ Mar 20, 2019 at 1:54
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    $\begingroup$ I'd say it's mainly no traffic, and at least in the middle latitudes, you can fly over anvils with decent margin and avoid most CAT, which is usually associated with jets that reside at the tropopause at frontal boundaries. If you're crossing the Atlantic, you can go straight across without having to run in the NA tracks which top out at 41. $\endgroup$
    – John K
    Mar 20, 2019 at 2:05

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