What is the highest altitude a B17 can fly?

The service ceiling was about 35,000 feet. Bomber raids would vary the height, to throw off enemy antiaircraft gunners. 25,000 to 30,000 feet was the norm. However, if the mission called for it, the bombers would go in much lower. The Ploesti raid in Rumania was at 500 to 1,000 feet. The Tokyo fire bomb raids in 1945 were at 5,000 feet.