Okay, so two things...1) Small commercial plane just makes it sound silly. It's a Cessna 152, right? lol 2) Two people on board AND towing a banner? Unless this aircraft has the 160 hp conversion, YIKES! Even if it does...2 people in a 152 SUCKS...talk about cramped!
Yeah, I had to laugh when they said small commercial airplane. When I hear small commercial airplane, I'm thinking a CRJ-100 or something like that. Anyway, I think you are right on it being a 152. Here is a pick of it being towed. http://media.nbcsandiego.com/images/PlaneTowed_0526.jpg
2 People ina 152 is quite cramped! why the heck were they towing in that thing?! Like you said, without the conversion.....no wonder they crashed. Hope everyone is alright!