Wikipedia:Reference desk/Archives/Science/2017 August 5

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August 5[edit]

Recent news[1] got me thinking: has there been cases of surface-to-surface missiles or rockets launched at a ground target that managed to accidentally hit an airborne aircraft? Mũeller (talk) 04:47, 5 August 2017 (UTC)[reply]

Yes. Especially mobile man carried versions meant to hit enemy tanks are at opportunity also used to shoot down helicopters. --Kharon (talk) 05:05, 5 August 2017 (UTC)[reply]
I appreciate English is not your first language but I think you should make sure you understand key words like wiktionary:accidentally before you try and answer questions like this. Nil Einne (talk) 05:22, 5 August 2017 (UTC)[reply]
No accidentally accidental collisions. --Kharon (talk) 06:00, 5 August 2017 (UTC)[reply]
What does that mean? It's not even a proper English sentence. Akld guy (talk) 06:42, 5 August 2017 (UTC)[reply]
Note that User:Kharon changed the word after I drew attention to it. Deceitful. I have restored the erroneous word and struck it out. Akld guy (talk) 09:16, 5 August 2017 (UTC)[reply]
Let's not be too hard on him, guys. He's just trying to help; his intentions are good. His response might not answer my question but is still very much appreciated. Mũeller (talk) 07:56, 5 August 2017 (UTC)[reply]
(EC) As Akld guy said your reply is unclear. Are you saying there have never been any accidental hits of an airborne target from a surface-to-surface missile or rockets? If so, what's your evidence? This seems to be the sort of thing really difficult to rule out. While an aircraft being hit is often a big deal, even just a helicopter, still there have been a lot of conflicts and countries sometimes prefer to keep details under wraps especially in friendly fire cases to save face etc. And even more so if we go to the pre-internet age, and consider non catastrophic damage, it this could have happened without it being widely known. Nowadays you can also include drones (I'm thinking the more commercial ones than the military ones) to further complicate the situation. Note that accidental doesn't have to mean almost random. For example, in a confused combat situation, it would seem possibly for an aircraft and a careless person targeting ground targets to be both involved leading to the potential for such an accident. I mean the Taiwanese managed to hit a fishing vessel AFAICT, probably without targeting it [2]. Nil Einne (talk) 08:08, 5 August 2017 (UTC)[reply]
The guided versions are actually not that common. Mostused ground to ground missiles are unguided ballistic versions, the socalled Rocket artillery or multiple launch rocket system (MLRS). Then there are the person carried versions. And then the motorized versions. Apart from the ballistic versions these missiles are mainly aimed to fight armored vehicles and thus have a very limited range. Newer BGM-71 TOW for example have a range of only 4,5 km. Airplanes typically fly much higher - especially the big ones. Additionally these and the ballistic ones are rather slow, compared to anti-air missiles. So the chances are very limited even if these missiles would be used constantly everywhere, which they are not. The only theoretically threat for planes would be the ballistic ones, because they go quite high when shot on long distances. But their use is also rather limited in wartimes. Our Atmosphere is simply a to big space for accidental collisions. Even Airplanes almost never collide with other airplanes, nomatter they all fly near eachother day and night in rather narrow "sky streets" between the few airport. --Kharon (talk) 09:13, 5 August 2017 (UTC)[reply]
Who said anything about guided? Or aeroplanes? You yourself seemed to already agreed that helicopters in flight are airborne aircraft and no has disagreed with you on the point. In fact as I pointed out drones (in flight), even the more commercial like ones, would also generally be considered so. So I'm not sure why you're suddenly restricting the question to aeroplanes. The only point of contention was you original talked about intentional targeting (of helicopters) when I pointed out the OP specifically asked about an accidental hit so intentional/opportunistic hits are not counted. You then suggested (I think), it had never happened but asked what evidence you have for this. I pointed out this seems to be something which would be very difficult to actually prove conclusively didn't happen. If by your own agreement helicopters are airborne aircrafts that can be intentionally hit by surface to surface missiles and rockets, then it seems plausible this could also happen accidentally in the chaos and confusion of wartime. And that it may not have been widely reported, especially if it was minor enough that the aircraft survived (or it was unmanned) and the side who owned the aircraft would perhaps prefer it not to be widely known even more so if it was a friendly fire incident so the side who hit it also feel the same and even more so in the pre-internet and information revolution age so even if it was reported in some local paper, there's a far greater chance no one noticed and picked it up because of how unusual it is. Note also that almost never is not never. The OP did not ask if it was common, simply if it ever happened. A single incident would mean 'no accidental collisions' would not be true. P.S. I should go back to the fishing ship case. Yes that was a 2D instead of 3D situation. But it was also a, from what I've read, completely accidental firing in a non combat something which in itself rarely happens. Which IMO further highlights why we should be very careful about assuming hitting something unintentionally never happens. Nil Einne (talk) 11:50, 5 August 2017 (UTC)[reply]
Anyhow, The Rocket Propelled Grenade by Gordon L. Rottman says: "...hundreds of helicopters [were] damaged or destroyed by RPGs in Vietnam..." but that threat only came to widespread attention after the Battle of Mogadishu (1993), when two Sikorsky UH-60 Black Hawk helicopters were shot down by shoulder-launched unguided RPGs. Alansplodge (talk) 14:25, 5 August 2017 (UTC)[reply]
Our List of accidents and incidents involving the Lockheed C-130 Hercules says: "April 7, 1979 : C-130H 116 of the Libyan Arab Air Force was shot down by an RPG-7 round during take-off from Entebbe, Uganda, which was subsequently captured by Tanzanian troops during the capture of Kampala". However, all of the above were probably intentional, but who knows? Alansplodge (talk) 14:34, 5 August 2017 (UTC)[reply]

Direct eye contact[edit]

As you know, some shy or otherwise modest people avoid prolonged direct eye contact. Does it really has to do with human evolution where our simian and more distant ancestors perceived staring as a sign of aggression and/or intention to attack (as observed in some modern mammals)? That said, does the ultimate cause lie in evolution and not in shyness or other personal traits? Thanks. 212.180.235.46 (talk) 08:59, 5 August 2017 (UTC)[reply]

Simply, a predator with good eyesight will always keep his prey in focus, when it sneaks up or waits for it and ofcourse also in the assult or hunt. Thus all higher lifeforms instinctively judge staring at them as danger or threat. Shy people simply instinctively signal the opposite intend to everyone by avoiding eye contact. --Kharon (talk) 09:30, 5 August 2017 (UTC)[reply]
methink you should had rather provided shyness and Eye contact (i couldn't believe this one exists, but it does!) for reference, as suits the ref desk Gem fr (talk) 11:27, 5 August 2017 (UTC)[reply]
An early stage of training in Scientology requires the student to confront a coacher eye-to-eye for two hours without blinking despite whatever the coach may do to "bullbait" (distract) him. The church says this is useful. Blooteuth (talk) 14:43, 5 August 2017 (UTC)[reply]
You can't literally "not blink" for anything close to that time. ←Baseball Bugs What's up, Doc? carrots→ 15:49, 5 August 2017 (UTC)[reply]
Yes, but Scientology promises perfect vision. You can throw away your eyeglasses, you won't need them. I guess you can throw away your eyelids too. ;) Wnt (talk) 16:04, 5 August 2017 (UTC)[reply]
But first you have to throw away your brain. ←Baseball Bugs What's up, Doc? carrots→ 17:19, 5 August 2017 (UTC)[reply]
The Man Who Stared for 41 Minutes. Blooteuth (talk) 17:40, 5 August 2017 (UTC)[reply]
There are also cultural variations. I spent part of my childhood in Hong Kong and Singapore, in whose local (predominantly Chinese) cultures (so I later read, and as is suggested in Section 6.2 of Gem fr's first and 5 of his second linked references above) looking directly into another's eyes is usual only in situations of intimacy or dominance/hostility. Having internalised this, as well as being somewhat shy by nature, I am in Western culture often perceived as "shifty" because I do not make eye contact as often as the local norm. (Possibly as a side effect, I also rarely notice or remember others' eye colour.) {The poster formerly known as 87.81.230.195} 90.202.208.125 (talk) 20:36, 5 August 2017 (UTC)[reply]