Aviation and aeronautical engineering Volume 7

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1919 Excerpt: ...panel. It is intended to prevent the loss of the bag in a storm while anchored and it is intended also to be used in landing in case the balloon breaks away from its mooring cable and starts on a free balloon flight. Types of Rip Panels Spherical Type.--A spherical balloon rip panel is perhaps the most vital part of the balloon. Without it safe landings cannot be made, except under the most favorable conditions. Envelope. Crosssection or Ba»s Showing Transverse F'aimel. Fig. 3 On landing the panel is ripped and the bag deflated quickly. Enough gas rushes out immediately to prevent the balloon rising off the ground after it once lands. If this were not the case, the balloon would strike the ground and rise again, repeating this several times, depending upon conditions, with great danger to the passengers. Many eases of spherical accidents due to defective panels have been recorded. Figs. 1 and 2 show a spherical rip panel of the type used in the latest Army and Navy sphericals. It is the outcome of gradual changes made from the experiences of many people and represents perhaps a very good type of spherical rip panel. Referring to Fig. 2, the slot cut hi the envelope is 4 in. wide and varies in length from 12% ft., for a small solo balloon, to 24% ft. for a 77,000 cu. ft. balloon. This slot is taped over the edge with 2-in. balloon tape. This allows one inch of the tape on both the inside and the outside of the envelope over the edge of the slot, gives the slot a smooth edge and prevents fraying. It is also a reinforcement against tearing. Before the edge of the slot is taped, in fact before the slot is cut in the bag at all, two reinforcements of balloon fabric are cemented, one on the inside and one on the outside of the bag. The outside reinforcement ...