But Meanwhile, One more difficulty had developed—with the tiles by themselves. As flight profiles ended up refined and aero-loads greater understood, engineers began to question whether the tiles could endure the punishment. By mid-1979, it had become noticeable that in selected places the tiles "did not have enough strength to https://www.facebook.com/permalink.php?story_fbid=pfbid02jAArigxVkBEZXSNgVpCS7cqWweu4SsWHBZ26UU6tFGHtNiqwE8ckgcEmqTbSGN2Ql&id=61562415773754&__cft__[0]=AZX_BCZxnuMA1RxyWH8Bi-yRF9rwBx5u2ktENoiePTkpV64ICIr_JRop4vSkPDmUoGBNflUdRhhpSW13o6UGYRfehZ8-b2vojIMg30gryCF9Mzo4bwUgCLHo2MwQoMfBixNe-zsGGziPDKIz3i-Rq-c4TRawaekylJ6ClA4SissJmPrO5RIMQ7_ChNUefQ0tN8eeVjVsfvJKOux6GoDA5scz&__tn__=%2CO%2CP-R