Cabin layout for 16 first class plus 108 economy class seats. 1 - passenger doors: 2 - doors for ground staff: 3 - buffet; 4 - clothes hanging space; 5 - washroom; 6 - supply compartment; 7 - cockpit; 8 - seats for stewardesses.
Interavia 10/1961 – Page 1,378
NAA Proposal for a Supersonic Transport
Technical Data
Powerplant
6 ducted fan engines
Thrust with secondary air-stream reheat
31,000 lb per engine
Thrust without secondary air-stream reheat
25,300 lb per engine
Main Dimensions
Span
104 ft
Length
198 ft
Top of fin from ground .
31 ft
Wing
Area
7,000 sq.ft.
Max. wing loading
61 lb/sq.ft.
Mean aerodynamic chord
75 ft
Aspect ratio
1.81
Leading edge sweep
65.67°
Dihedral
0°
Flaps
490 sq.ft.
Control Surfaces
Canard Area
410 sq.ft.
Sweep (25% chord). . .
38°
Dihedral
0°
Flaps
54 sq.ft.
Vertical fins (two) Area .
2 x 255 sq.ft.
Sweep (25% chord)
45°
Fuselage
Max. width (overall)
12 ft. 4 in.
Max height (overall)
9 ft. 2 in.
Cabin length (incl. subsidiary compartments)
89 ft 8 in
Cabin Width
11 ft
Cabin Height
7 ft
Gangway width (1st Class)
23 in
Gangway width (Economy Class)
15 in.
Cargo compartment Capacity
1,000 cu.ft.
Weights
Total structure.....
122,800 lb
Total power plant . . .
50,800 lb
Total equipment ....
30,400 lb
Manufacturing weight
204,000 lb (1)
Max. takeoff grossweight
439,000 lb
Max. landing weight . .
300,000 lb
Max. zero fuel weight. .
260,000 lb
Max. usable fuel ....
217,000 lb (2)
Performance
Cruise speed equivalent to
Mach 3
at average altitude of
68,000 ft.
Critical field length
6,200 ft. (3)
7,900 ft (4)
Landing runway required
7,950 ft. (5)
8,600 ft. (6)
1.) For the 108 economy class and 16 first class seat version. For variations in cabin class 27 lb per economy class and 32 lb per first class seat must be allowed.
2.) 32,400 US Gal. at 6.7 lb per gal.
3.) According to SR 422B; max. takeoff gross weight; sea level; 100°F.
4.) As 3, but 3,000 ft above sea level.
5) According to SR 422B; 40 percent reverse thrust on three engines during ground roll; maximum landing weight; sea level.
6) As 5, but 3,000 ft above sea level.
As an example of the various projects for a Mach 3 transport prepared by American constructors, we have selected here that of North American, concerning which some details were recently announced.
As North American stresses, this is only a paper study, which is subject to continuous alteration. The first efforts of the NAA engineers arc being directed towards reducing takeoff weight by light construction methods and aerodynamic improvements, in order to cut down fuel consumption and reduce operating costs. Later modifications should also enable economic employment of the aircraft on shorter routes at low supersonic, or even subsonic, speeds. Despite their provisional nature, the data available concerning NAA's preliminary design are of interest and are suitable as a basis for operational investigations and commercial calculations.
As is to be expected, this design is inspired (it is not alone in this) by the B-70 Valkyrie Mach 3 bomber. but is fully tuned to civil requirements. The calculated operating costs are comparable to those of today's long-haul jets for 3,500 mile block distances. The run-ways normally available at international airports are adequate for takeoff and landing. And, thanks to the "quiet" but high thrust turbofans, climb performance is good, and there will be little reason for those living in the vicinity of airports to complain of excessive noise. If sound pressure at ground level is not to exceed 1.46 lb/sq. ft, the aircraft must not pierce the sound barrier below 34,000 ft.
Features of Design
North American selects the following features of its design as important:
1. Trimmable canard control surfaces.
2. Spoilers and air brakes.
3 .Downward folding wing tips for economic cruise flight.
4 .Braised stainless steel honeycomb sandwich and riveted titanium sheet construction.
5. Six duct-burning turbofan engines with thrust reversers. 6. Multi-shock induction system —one to each three engines.
7.. Main undercarriage legs each with 8-wheel bogie, tire. pressure 160 p.s.i.
8. 4,000 p.s.i. hydraulic system with brazed fittings.
9., Fully powered automatic hydraulic control system.
10.. Closed-cycle air-conditioning system for the cabin, with ram air pressurization for emergency use.
11. 115/200 volt, 400 cycle, 3 phase AC electrical system.
12 System checkout during flight.
13 Crew vision angles in accordance with current US regulations (CAR 4b).
14. Self-contained hoists for facilitating loading and unloading of 224 in x 110 in .x 76 in freight compartment (usable cargo space 1,000 cu. ft).
Flight Profile
The assumptions used in the calculation of times, speeds and fuel consumption are as follows: climb at subsonic speed to about 43,000 ft; transonic accelera-tion in climb to supersonic speed; attainment of Mach 3 at minimum cruise altitude; continuous climb at Mach 3; average cruise altitude about 70,000 ft; deceleration to subsonic speed at an altitude of at least 43.000 ft; approach flight and landing; plus six minutes manoeuvre allowance. For a block distance of 3,400 n.m. to be accom-plished with maximum payload, resultant block time, (which includes 15 minutes taxiing time), is 2 hrs 45 mins, block speed 1,240 knots, and block fuel consumption (during flight plus 5.000 lb in taxiing) 176,000 lb.
If the aircraft is forced to deviate to an alternative airport, the amount of fuel used at most favourable cruise altitude, at an all-up weight of 300,000 lb and under ISA conditions, is about 1,050 lb per min. If holding at the airport of destination becomes necessary, the fuel requirement at most favourable Mach no. holding flight, with an all-up weight of 250,000 lb at an altitude of 25,000 ft is about 400 lb per minute, and at sea level some 490 lb.
Typical Operational Weight Calculation
This example is based on a block distance of 3,400 n.m., e.g. New York/Zurich, with max. payload. Cabin layout: 16 first class and 108 tourist class passengers.
lb
Manufacturing Weight Empty
204,000
Crew (8 Persons plus Baggage)
1,580
Unusuable Fuel and Oil
1,400
Cooling Water
2,000
Engine Oil
285
Liquid Nitrogen Fuel System
400
Flight supplies, emergency equipment etc
1,945
Operating weight empty (rounded values)
212,000
Payload (Passengers, baggage, freight)
31,000
Operating Zero fuel Weight
243,000
Reserve fuel (for 300 n.m. diversion at cruise altitude plus 30 minutes hold at sea level
25,000
Operating Landing Weight
268,000
Flight Fuel
171.000
Maximum all-up weight
439,000