Iraq SAM Questions

http://www.news24.com/News24/World/Iraq/0,,2-10-1460_1449430,00.html
Missile hits DHL plane
22/11/2003 19:21 – (SA)
Baghdad – A civilian plane belonging to international express courier DHL made an emergency landing in Baghdad on Saturday after being hit by a surface-to-air missile in the first successful strike on a plane of the seven-month-old Iraq insurgency.
Nobody was injured in the attack, but it prompted Jordanian carrier Royal Wings, the only airline to offer civilian passenger flights into Baghdad, to suspend its service.
A spokesman for DHL said it was still too early to make any announcement on the future of its own cargo service.
“A DHL plane took off from Baghdad airport this morning and was hit by a SAM-7 surface-to-air missile,” said a US military official who asked not to be identified.
“It caught fire, it turned around and came back to the airport where it safely landed. The fire was taken out.”
Basim al-Waziri, a resident of the southern Yusifiyeh area of the capital, said he saw the missile being fired on the aircraft and hitting its left wing, setting it ablaze.
DHL, the formerly US-owned courier now owned by German giant Deutsche Post, confirmed that its staff had suffered no injuries.
Company spokesman Patricia Thomson said the Airbus A300 freighter had been flying from Baghdad to DHL’s Gulf hub in Bahrain when it was forced to return to the Iraqi capital at around 9:30 am.

My question… What was the missile doing? I mean, aren’t most SAMs supposed to go for a heat source? Is there a slight possibility that is was optically guided?
The pictures I have seen show the port wing flaming but well outboard of the engine – so could the missile have utilised a proximity fuse?
Anybody know what height the Airbus was? The Strela-2 used in Mombasa last year has a maximum altitude of 2,000metres – is this enough?

Just a thought, that’s all…

Flood.