The over-all de-icing characteristics of two of the boots investigated were quite similar. The de-icing protection afforded by the boot having small unheated areas existing between segments was slightly less than that of the other two boots. The over-all runback characteristics of the boots were similar for the icing conditions under which the performance was evaluated. The critical areas for all boots investigated were the most forward cycled segments on the upper and lower surfaces (located adjacent to the parting strip). While operating at design power densities and at an angle of attack of 2°, the range of free-stream total temperatures at which the icing protection afforded by the various boots became marginal was from 12° to 15° F for an icing condition having a free-stream velocity of approximately 395 feet per second, a liquid-water content of 0.5 to 0.6 gram per cubic meter, and a droplet diameter from 12 to 14 microns.
展开▼
