OK, I know this is a thread drift but I'll be quick.... The photo in Post #8 of a Chinook carrying a stripped-down DC3 reminded my of a very similar event I witnessed when I was working for Bristow in Iran. It was at the Galle Morghe airfield in the south of Tehran, I heard the distinctive sound of a Chinook and went outside just in time to see the Chinook place the DC3 on the ground very gently, BUT, whoever rigged the DC3 used a VERY big drogue parachute to keep it stable. I'm sure it worked well - until the Chinook pilot released the hook - at this point the downwash kept the drogue chute deployed and, slowly but surely, the DC3 began to roll backwards. It accelerated slowly then slowed as the Chinook climbed away. It rolled some 30-40 meters and came to a halt without hitting anything.
The comment in Post #9 about lashing a 747 flap section laterally across the floor also reminds me of the time, again in Iran, when I was working on a seismic operation in the marshes at the southern end of the Iran/Iraq border. the customers personnel moved around in locally-hired canoes which were about 7-8 meters long. These were too difficult (and fragile) to sling-load so we would open both sliding doors of the 205/212 and lash them to the floor - never had a problem.