The whole issue is based on edited news footage. It was filmed for a full 10 minutes according to the cameraman. Based on that edited footage many observers were asked to comment. It was based purely on it looks like a ballistic missile plume and what appeared to have been a rocket engine. Consider that the airliner travelling at 37,000 feet was reflecting the light as it transited towards the coastline? The airliner produced a persistent contrail and as it approaches the coast the persistent contrail dissipates into a non-persistent one. Notice how reflections can produce glare from the underside of the fuselage on these airliners.
Copy and paste if the links don't form.
http://www.youtube.com/watch?v=PxnnRvYoxRY
http://www.youtube.com/watch?v=N_N5ZgYzj44
The cameraman has already been fooled by perspective so he is also being fooled by glare and reflection as the airliner travels towards the coast. If you look at the video the glare is filmed when the airliner is still producing the persistent contrail. This shows how far out the optics on the helicopter were recording this airliner. The optics were also producing massive foreshortening at that distance.
The airliner persistent contrail (horizontal) was captuted by a weather satellite.
A classic example of how an edited video, a camerman being fooled by perspective and a media frenzy can generate into a full blown conspiracy.