80、The fuel vent system keeps the pressure of the fuel tanks near the ambient pressure. Too large a pressuredifference can cause damage to the wing structure.

燃油排放系统保持油箱压力接近环境压力。太大的压力会引起机翼结构损坏。

燃油通风系统保持油箱压力接近大气压力。压差过大会引起机翼结构损坏。

燃油通风系统确保油箱压力在接近大气压时保持稳定。太大的压力变化会引起机翼结构损坏

正确答案：B

1400、向跑道进近过程中,航道指示器上的偏航指计指示飞行员必须向哪个方向操纵飞机。

1399、在补片表面施加重量以确保各部件正确粘接。

1398、Light Ll comes on in 3 seconds or less

1397、It is necessary to clean the filter periodically.

1396、This part provides for a uniform method of arranging and identifying specific subject material.

1395、During the approach to the runway deviation pointers in the course indicators show the pilot in which direction theaircraft must go.

1394、Make sure that the fuel load is equal on each side of the aircraft centerline;

1393、Repeat application of clean solvent as necessary to remove oils.

1392、Outlets along the side walls and the center of the ceiling divide the air for symmetrical supply.

1391、Equivalent substitutes can be used.