I don't know what the actual rule is but it is true.
It is fallout from that SAA crash a few years back where they lost a 747 combi to what is belived to have been a cargo fire.
The FAA since then has really tighted up the rules on hauling freight. Freight now can't stick out from beyond the edges of an igloo, your flats with loads on them have to be covered in pretty expensive fireproof blankets.
It is actually a pain in the ass.
I know a company up here that operates a rather large bush airplane, 19 seats. They wanted it to operate as a 9 seat combi, that way they could fly in hunting parties and their four-wheelers and other bulky gear.
They where able to get a copy of an STC from another operator on the field that flew the same aircraft. The STC involved doign just what the company wanted, and was allready approved in the other operators equiptment. The STC convered mainly installation of smoke detection equiptment and a partion to seperate the passengers from the freight.
Using that data the first company put in for the STC, and where reject. Didn't matter that it was allready approved and in use on another aircraft. So now the first company is at a distinct disadvantage on chartering out aircraft to the other company.
I still haven't figured out what made the installation in company B's aircraft so much safer then the one that was proposed in company A's airplane.
OBAMA-WORST PRESIDENT EVER....Even SKOORB would be better.