"Listen, it is easy to laugh now, post fact and point out that it was obvious that airspace should have been closed."
now? There is a ukrainian member here on PPRune that wondered why that airspace isn't closed 10-15 days before the crash, and you can be sure there were many professionals (military and civilian) in Ukraine that wondered the same. Why that decision was not brought is anybodys guess.
"These darn things will either struggle to get above 15k .....or they won't struggle at all ....."
BUK will go to around 50K so only Concorde should be safe...oh wait we ditched it because of noise and costs that didn't pose problems half a century ago.
"As in most things military, maximum performance figures are highly classified and depend on a multitude of factors. Ranges for MANPADs generally assume the target is high performance aircraft that can maneuver aggressively and deploy countermeasures (chaff, flares, jamming) in response to onboard and remote (e.g. AWACS) tracking, lockon, and/or launch warnings. Indeed, defeating a MANPAD these days is often more about geometry and maneuvers (at 6 to 9Gs) to bleed the missile of its finite supply of kinetic energy, something commercial aircraft are unable to do."
except israeli El Al...and people were mocking them about that, now I don't say those would 100% work against SA-11(as those countermeasures are designed with MANPADs in mind) but survivability percentage would be significantly higher