USS Macon

Hard to believe this was the best way to build such an immense vehicle... long ladders balanced on carriages. 

From Wikipedia:

Leading up to the crash

During a crossing of the continent, Macon was forced to fly up to 6,000 ft (1,800 m) to clear mountains in Arizona. As the ship's pressure height—the height at which the gas cells would start to leak and eventually rupture due to pressure difference—was less than 3,000 ft (910 m), a large amount of helium was vented to reach this altitude without rupturing the gas cells. To compensate for the loss of lift, 9,000 lb (4,100 kg) of ballast and 7,000 lb (3,200 kg) of fuel had to be dumped. Macon was being flown 15,000 lb (6,800 kg) "heavy" and was operating at full power not only in order to have sufficient dynamic lift, but to have enough control to fly in the severe turbulence through a mountain pass near Van Horn, Texas. Following a severe drop, a diagonal girder in ring 17.5, which supported the forward fin attachment points, failed. Rapid damage control by Chief Boatswain's Mate Robert Davis repaired the girders before further failures could occur. Macon completed the journey safely but the buckled ring and all four tailfins were deemed in need of strengthening. The appropriate girders adjacent to the horizontal and lower fins were repaired, but the repair to the girders on either side of the top fin were delayed until the next scheduled overhaul when the adjacent gas cells could be deflated.


On February 12, 1935, the repair process was still incomplete when, returning to Sunnyvale from fleet maneuvers, Macon ran into a storm off Point Sur, California. During the storm, she was caught in a wind shear which caused structural failure of the unstrengthened ring (17.5) to which the upper tailfin was attached. The fin failed to the side and was carried away. Pieces of structure punctured the rear gas cells and caused gas leakage. Acting rapidly and on fragmentary information an immediate and massive discharge of ballast was ordered. Control was lost and, tail heavy and with engines running full speed ahead, Macon rose past the pressure height and kept going until enough helium was vented to cancel the lift. It took her 20 minutes to descend from 4,850 ft (1,480 m) and, settling gently into the sea, Macon sank off Monterey Bay. Only two crewmembers died from her complement of 76, thanks to the warm conditions and the introduction of life jackets and inflatable rafts after the Akron tragedy. The two that perished did so needlessly: Radioman 1st Class Ernest Edwin Dailey jumped ship after she had lost most of her altitude but was still high above the ocean surface; Mess Attendant 1st Class Florentino Edquiba drowned while swimming back into the wreckage to try to retrieve personal belongings. An officer was rescued when Commander Wiley swam to his aid, an action for which he was later decorated.

The cause of the loss was operator error following the structural failure and loss of the fin. Had the ship not been driven over pressure height (where the cells were expanded fully and lifting gas released) Macon could have made it back to Moffett Field. Four Sparrowhawks carried aboard were lost with the airship.

Macon, having completed 50 flights from her commissioning date, was stricken from the Navy list on February 26, 1935. Subsequent airships for Navy use were of a nonrigid design.


One cool aspect of the Akron and Macon were the Hangar bays that would allow Biplanes to drop from the main hull. I dont know about you, but this has my juices flowing. 

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