Wikipedia:Featured picture candidates/Sonic boom

Sonic boom

Voting period is over. Please don't add any new votes. Voting period ends on 22 Oct 2010 at 00:17:30 (UTC)

Original - ~~Sonic boom~~ Condensation appearing during a transonic flight. (description)

Alt1

Alt2 description

Alt3 (withdrawn)

Alt4 description

Alt5 description

Reason: There are a few images of sonic boom of high EV available, and I think one of them should be featured
Articles in which this image appears: ~~Sonic boom~~Transonic
Category: Wikipedia:Featured pictures/Sciences/Others or Wikipedia:Featured pictures/Vehicles/Air
Creator: N.A.

Support as nominator --Nergaal (talk) 00:17, 13 October 2010 (UTC)[reply]

I think the original is the best, but some might think others are better. I listed 5 others that are of high resolution. Nergaal (talk) 00:27, 13 October 2010 (UTC)[reply]

Caution These zones of condensation are routinely produced also at subsonic speeds; it happens all the time, especially at low level. The only instances that are clearly at supersonic speeds are those that clearly angle back at more than a 45° angle. Alt3 showing the F‑18 is clearly at subsonic speed. It appears to me that Alt5 showing an F‑14 might be going supersonic, but it’s hard to tell for sure. Given however, that its wings are swept back, it’s at higher altitude, and you can see shock diamonds associated with being in full afterburner all suggest it’s certainly at least trying to go fast.
I am afraid that only a very authoritative source (like a military Web site that flat says so) can establish whether any of these are supersonic; you can’t rely upon news sources (traditionally RSs) because reporters are usually technical “dudes” on this sort of stuff but have been given a computer on which they can bang on. And you certainly can’t base it off a photo’s title unless you can track the provenance all the way back to a technically authoritative source. The exception are reporters for Aviation Week & Space Technology (a magazine I subscribe to) because many of those writers are pilots—often ex-military pilots. Greg L (talk) 00:48, 13 October 2010 (UTC)[reply]

Original description for alt4 seems to say that. Nergaal (talk)

Alt5 and original don't clearly say it. Rm alt3. Nergaal (talk) 01:03, 13 October 2010 (UTC)[reply]

Very well, Alt4 is a valid candidate for consideration. I hope the Navy PR dude was correct, because low-level passes near ships are seldom at supersonic speeds. In fact, I know of no cases. But it’s hard to prove a negative. Please don’t delete pictures as we have started discussion and it is important to have the full variety here now. Just add “(withdrawn)” in its caption. Greg L (talk) 01:05, 13 October 2010 (UTC)[reply]

I've looked through the navy.mil 's gallery and the only place I could find the an explicit direct statement of sonic boom is here; but if anything, that picture isn't very informative. This, this, this and this don't directly state it. Nergaal (talk) 01:22, 13 October 2010 (UTC)[reply]

The description for alt2 also. Nergaal (talk) 02:11, 13 October 2010 (UTC)[reply]

Comment: What's the deal with all the alts? Only one of the nominated images is actually used in the article. It's not FPC's job to adjudicate which image should be used in an article. J Milburn (talk) 18:21, 13 October 2010 (UTC)[reply]

Ut could be nominated as a set. Spongie555 (talk) 21:08, 13 October 2010 (UTC)[reply]

Hardly- they're just a bunch of images showing similar subject matter, not a closed set. In any case, that doesn't change the fact that some of them are completely unused... J Milburn (talk) 22:18, 13 October 2010 (UTC)[reply]

Note since nominating these images I have realized that it is a bit tricky to count any of them as sonic booms at 100% probability. Instead, all of them show transonic speeds, and they have high EV for that. I think it would be more appropriate to call this nom something like "Transonic" or "Transonic speeds" instead of "Sonic boom". And yes, if people are ok with it, they (or a part of them) could be used as a set. Nergaal (talk) 21:47, 13 October 2010 (UTC)[reply]
- Honestly? Badly thought out nomination. Nominate a picture that has high EV and is of high quality. Don't throw loads of similar images at the process and hope something sticks- it creates difficult nominations, upset and the possibility that something gets promoted which really shouldn't have been because of the way the numbers stack... The article you claim these images add to does not use most of them, and is led by File:FA-18 Hornet breaking sound barrier (7 July 1999).jpg, which is a previous FP. The ones that are used are tacked on to the bottom of the article as an afterthought. J Milburn (talk) 22:18, 13 October 2010 (UTC)[reply]
  - I guess I did not make my point very well. Feel free to remove the nom from the list as I don't think it is worth my time trying to convince that these pics have good EV value if that has not gotten though until now. Nergaal (talk) 22:41, 13 October 2010 (UTC)[reply]

If I may be so bold, Nergaal seems a bit new to this venue, but his above post can be interpreted as “Nomination withdrawn”; correct me if I am wrong, Nergaal.
I agree with your technical assessment that these are likely all transonic. Sonic booms are little understood by most people. One can often find newspapers with stories from the AP where the caption says something like “This photo shows the moment the plane broke the speed of sound.” The underlying assumption is that a sonic boom signifies the instant a plane “crashed through” a barrier known as the speed of sound. Of course, the entire time a plane flies at greater the speed of sound, it is dragging its shock wave along the ground exposing anyone near its path to the double-boom. Moreover, the double-boom is the product of a shock off the nose of the plane as well as its tail. The reason such short vehicles going so fast can have booms a significant fraction of a second apart is the two shock fronts are at slightly different airspeeds and therefore spread out at a different angle (I think I have that bit correct). Anyway…
I would expect a photo of a sonic boom to show both these shock fronts. Alas, the only photographs I know of that truly illustrate a sonic boom are schlieren photographs like this one.
I’m glad to see that our “Sonic boom” article has the phenomenon illustrated here in this nom (the Prandtl–Glauert singularity) properly explained in the photo caption in that article.
This is also instructive about relying upon supposedly (seemingly?) reliable sources for the facts on technical issues. Two of the above photographs traced to Navy PR pages with captions about how the planes were flying supersonically. If you ever visited the department responsible for those PR releases and saw how things work, you’d understand. Greg L (talk) 00:11, 14 October 2010 (UTC)[reply]

Yes, I think this nom looks like a dead horse. I thought initially that the original was cool; but in the end the nom just got confusing to reviewers. Nergaal (talk) 06:59, 14 October 2010 (UTC)[reply]

Yeah- if one of these is of high quality and has a solid use within an article, feel free to nominate it, but mass nominations like this are not a good thing. J Milburn (talk) 10:41, 14 October 2010 (UTC)[reply]

Comment Maybe Prandtl-Glauert singularity is worth a look. Noodle snacks (talk) 06:53, 15 October 2010 (UTC)[reply]

Not promoted Withdrawn. —Maedin\^talk 12:27, 20 October 2010 (UTC)[reply]