1 Discard any hammer with mushroomed or chipped face or with cracks in the claw or eye sections. 2  Wear safety glasses or goggles, or a face shield (with safety glasses or goggles).  Strike a hammer blow squarely with the striking face parallel to the surface being struck.
The first jet airplane was the Heinkel He 178 made in Germany in 1939, right before the outbreak of World War II .
The first Whittle engine successfully flew in April, 1937. This engine featured a multistage compressor, and a combustion chamber, a single stage turbine and a nozzle. â¢ The first jet airplane to successfully use this type of engine was the German Heinkel He 178 invented by Hans Von Ohain. It was the world's first turbojet powered flight. â¢ General Electric for the US Army Air Force built the first American jet plane. It was the XP-59A experimental aircraft.