FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1964
1964 - 1997.PDF
22 This drawing has been prepared by one of our editorial artists with the co- operation of the Los Angeles Division of North American Aviation Inc. The chief difficulty which he encountered was that the 8-70 is so large that structural details cannot be shown in the main drawing, and accordingly there are an unusually large number of detail insets. The subject of the drawing is the first of the two X&-70A aircraft (US Air Force serial number 62-0001), which art equipped for a flight crew of two B.7O . . . "transpiration" wall and ducted back into the Freon heat exchanger after passing through a water-vaporizer heat exchanger. Water for the vaporizer is contained in a large cylindrical tank aft of the pilots. A similar tank full of liquid ammonia provides an auxiliary supply for use at the end of a long mission when the water tank is empty. The plenum chamber is insulated from the 470°F outer skin by 2in of glass-wool on the inside face of the skin, a dead air gap and finally a thinner glass-wool layer with a surface temperature of 150°F. During the cycle, cabin air heats to 90-100°F after emerging from the refrigeration system. At that temperature it flows through the 102°F transpiration wall at the rate of O.?lb/min/sq ft. As the cooling air flows through the plenum it rises to a temperature of 114°F before recycling through the heat exchangers. In this way the temperature of the crew compartment is maintained at 70° to 100cF, and the electronic equipment compartment at 130° to 160°F. Fuel/water heat exchangers in tank No 3 provide cooling for the "water walls" of compartments such as the landing-gear and drag chute. Electrical Power An all alternating-current electrical power system is used on the XB-70A. The decision to use a 115V to 200V, 400c/s bus system powered by two 240/416V primary generators came after studies indicated that considerable weight could be saved by abandoning conventional d.c. power. As has been realized for some time, 400c/s a.c. devices weigh considerably less than their d.c. counter- parts. Power transmission at full generator voltage also proved considerably lighter, although transformers located near the load centres are still required to step generator voltage down to bus level. The electrical system is conventional in layout, consisting of Reteasable information includes the following: engines, six 31 .OOOIb-thrust General Electric YJ93-3 turbojets: span. WSft (tips spread); length, 185ft 196ft with instrumentation boom); wing area, 6,300 sq ft; gross weight, approximately 530,0001b; design cruising Mach number, 3.0 (1,980 m.p.h.); range at Mach 3, between 6,000 and 9,000 miles 1 Retractable vizor (see inset) 2 Two-position outer windscreen 3 Inner pressure-bearing windscreen 4 Crew door 5 Escape capsule 6 Parachute packT Window 8 Clamshell blast doors 9 Escape hatch 10 Closed and ejected capsule: roci<et burnout 0.5sec, trajectory peak -f 325ft at l.9sec and parachute open at 9sec; 28ft/sec landing 11 Stabilizers 12 Control runs 13 Radio and electronics 14 Recording systems, digital and analogue compjters (ahead of weapons bay) 15 Flight-control system electronics, recorders, gust recorder 16 Cabin air system 17 Overboard spill from (16) 18 Ammonia and water 19 Fuselage fuel tanks (shaded; also see inset) 20 Wing tanks (shaded; also see inset) 21 Fuel distributed around ducts 22 Main-gear bay 23 Bay-cooling water (alternative ethy- lene-glycol) circulation 24 Multi-disc bra«es (80 surfaces) 25 Braxing-system reference wheel 26 High-temperature tyres 27 Tandem steering cylinders 28 Pre-closing doors 29 Variable-geometry intake throat 30 Actuators for perforated, hinged . walls 31 Boundary-layer bleed (exit below) 32 Trimming and bleed doors in duct roof 33 All-moving canard foreplane (stab- ilizer), 0° to +6° 34 Foreplane actuators 35 Canard flaps, 0" to 20° down
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
