251 trường hợp nhiễm Covid-19

251 trường hợp nhiễm Covid-19

Kết quả (Anh) 1:

251 cases Covid-19

Kết quả (Anh) 2:

Started the engines with compressed air and spark from a high voltage transformer. Just Thirty seconds before launch time, with the engines at full speed, considerable sparking began coming out of the right tailpipe. Nonetheless, the countdown continued and the JB-1 roared down the track at two hundred thirty feet per second. The jet bomb departed the launch cart and nosed up to a forty-five degree angle, climbing rapidly until the wing stalled and the missile crashed into the surf after a five-second, four-hundred-yard dash from the ramp. Salvage revealed the source of the engine sparks during the launch sequence to be the shearing off of half of the turbo blades. Engineers determined the elevons being set at too great a positive angle caused the steep climb and stall. By December 21, after extensive review, Northrop decided to drop the General Electric turbo jets in favor of the more reliable and proven pulse-jet engine of the JB-2. This design change resulted in the close of the JB-1 designation with only one unit produced and tested, and led to the production of the JB-10 which incorporated a single pulse-jet engine in the center of the missile's fuselage surrounded by a special cooling shroud. Testing of the JB-10 would follow in 1945, but also ended in failure. 69
The Ten jet bomb projects included a broad range of designs. However, the Technical Service Command cancelled four of the JB missiles (JB-5, JB-6, JB-7 and JB-9) in the concept or design phase. Hughes Aircraft developed the JB-3 (MX-570) Tiamat subsonic air-to-air missile. Test launched from the ground and from an A-26 aircraft, this design featured three large fins at the tail with active control surfaces. The JB-4 (MX-607), essentially a modification of the existing GB-4 guided Glide bomb, featured a Ford PJ31 pulse-jet engine. The JB-5 (MX-595) designers envisioned an unguided, wingless ...

Kết quả (Anh) 3:

251 case of Covid-19-19.