SR71A REFERENCE INFORMATION
Revised October 2012

For standard procedures, see the Checklists tab.

Speeds vary widely depending on temperature, pressure, altitude, wind, takeoff weight, runway length, runway slope, and runway conditions. Pilots calculate speeds and fuel load using complicated charts and tables. The speeds below are approximations. All specifications assume no changes to dynamics or default loading as provided in distribution. FS9/X FLIGHT DYNAMICS OPTIONS ALL SET TO MAX REALITY and IAS option set (not "true".)

!!!! DO NOT EXCEED: !!!!
-> +5.5 deg pitch above 60Kft or Mach 3 (high drag/dynamic stall)
-> Mach 3.45 (overspeed)
-> 500 KEAS (overspeed)
-> Under 310 KEAS level or climbing while supersonic
-> Less than 6100 RPM over Mach 1.5 (compressor stall)
-> 427C CIT

!!    AVOID:    !!
-> Under 365 *KEAS* while descending above Mach 1.5
-> COG out of published limits
-> Static temps at cruise warmer than -50C or 
colder than -75C.
-> Atmospheric Pressure under 29.45
-> Speed/COG with level Pitch Trim 
more nose down than -1.5 (rear heavy)
Slow down, climb or pump forward if trim warning.
-> Less than 0 deg AOA level cruise
-> Derich OFF in warm temps or high mach

Climb Schedules:
The SR-71 uses two climb "schedules" (or speeds.) Which one you use depends on the type of flight you are making.
400 KEAS is used for longer flights where fast climb and fuel saving is more important than speed.
450 KEAS (normal) is used when speed is more important than fuel range and altitude during the climb.
Both start out after take off using the usual speed restrictions (if any) or 400 KEAS.
In the Mach climb (or after the Dipsey Doodle) the pilot will set an initial 470 KIAS on the AP bug for a target of 400 KEAS OR 530 IAS on the AP bug for an initial target of 450 KEAS, then activate KEAS Hold when crossing these speeds.
Please consult the provided HTML manual for additional information.

---- MISC SPEC ----
Typical Static Temp operating range at 80Kft:
-50C to -75C
Note: Mach Cruise outside this range will have
noticeable impact on eng power and fuel efficiency.

Wing Span: 55 ft 7 inches

Total Length: 107 ft 5 inches (including probe)

Total Flight Simulator aircraft weight with full fuel:
172,000 lbs.

Thrust at sea level (per engine):
32,500 lbs static.
45,000 lbs W/AB.

Fuel Rate Idle (total):
4K-6K lbs/hr
Fuel Rate (Full AB Take-off):
40-50K lbs/hr
Fuel Rate Cruise:
35K - 40K lbs/hr

---- FLIGHT LIMITS and BALANCE ----
Max Taxi Speed:
40 MPH (35 KIAS)

Min Take Off Runway length: 9,000ft.
(full weight with reheat)
The minimum permitted takeoff run and landing
distance available:
2,000m (8,000 feet).
Min land Runway length: 7000ft @MLW
Typical Take off distance (45K lbs fuel):
4,800ft

Max Climb from Take Off:
10,000ft/min (AP) or 11,810 ft/min manual.

Normal Cruise Speed (Vc):
400 KIAS/350 KEAS (Mach 3.2) @ 80,000ft.
Typical Cruise RPM: 7050-7150

Descent Speed:
365 KAES while above Mach 1.5

Descent Rate:
up to -6200 ft/min while above Mach 1.5

VMO - Maximum Operating Speed (KIAS):
500 KEAS @ 65K ft
vL - Design Speed:
350 KEAS (400 KIAS), Mach 3.20

MMO - Maximum Operating Speed (Mach):
Mach .65 - 1.07 (5,000' - 32,000' MSL)
1.75 - 2.0 (44,000' - 50,000' MSL)
3.32 (51,000 - 85,000' MSL)
Model Overspeed:
500 KEAS, 556 KIAS, Mach 3.45

Dynamic Mach Stall:
Speeds near Mach 3 but below 280 KIAS
Note: Panel Warning when above Mach 2.6 but below 300 KIAS.

Compressor Stall:
Under 300 KIAS while above Mach 1.5
Under 350 KEAS while descending.
Eng RPM under 6100.

VLA - Lowest Authorized Speed (level):
175 KIAS (5,000' - 20,000' MSL)

Min Turn Speed:
220 KIAS (level)

G Limits (spike fully extended):
+3.2
-1.9
Note: Spike retraction increases G force damage sensitivity by ~ 5%

Flight AOA Limits:
Max below 25K ft = 18 deg
Max Subsonic 25K+ ft = +10 deg
Max Supersonic 25K+ ft to 70K ft = +8 deg
Max Supersonic 70,000+ ft = +6 deg

Max Turbulent penetration speed (subsonic):
350 KEAS
Typical Subsonic Climb Speed:
400 KEAS
Climb abort speed:
350 KIAS
Minimum AOA during climb:
.5 deg @ M2.6, never below zero when faster.

Typical Supersonic Climb:
350 KEAS Hold or 400 KEAS Hold

COG:
Modeled MAC in FS2004 = 60.5 ft (wing + forward fuselage chine).
Typical range: +17 to + 24
Max at cruise: +25% (automatic system peaks +24.97%)
Max Take off and land: 22 %
Max below Mach 0.9: +24%
Min COG above Mach 1.8 and 11,570 lbs fuel: +17%
Min below Mach 1.8 and 11,570 lbs fuel: +14.5
Mach 3.30 = 24.3 % MAC
Ideal COG Table:
Gross Weight lbs  
% 130-140K          20-22
120-130K              22-24
90-120K                24+

---- ENGINE ----
Spike:
Subsonic to Mach 1.69 = spike full forward zero inches (F5)
Mach 1.7 to Mach 2.04 = 1 - 6.4 inches
Mach 2.05 to Mach 2.42 = 6.5 = 12 inches
Mach 2.43 to Mach 2.75 = 13 - 19.4 inches
Mach 2.76 to 3.10 = 19.5 - 25 inches
Mach 3.11+ = 26 inches
(F8 full engine spike retraction)

EGT:
Max start temp= 565 C (near 95 deg F static)
Target Optimum performance EGT:
775 deg F - 805 deg F
Normal Cruise Range: 780 - 820C
Continuous Limit: 830C
Emergency Zone Start = 805 C | up to 15 minutes
Emergency Zone Limit = 845 C |
Red Zone : 900 C up to 2 minutes
950 C up to 15 seconds
Note: Panel warnings at 845C and 900C
Optimum Descent EGT:
700C (1,292 F)

Max Inlet Temperature (CIT):
427C (801F)
Typical M 3.2: ~ 350 C

Max Eng RPM:
7450

Oil Pressure:
Min: 35 PSI
Normal: 40-60 psi

Max Oil Temperature:
177C

---- ----

---- TAKE OFF ----
Maximum authorized takeoff weight: 172,000 lbs.

Max Gear Retraction/Extension/Down Speed:
350 KAES/320 KIAS/Mach 0.7

V1 - Generalized Runway Decision Speed: 150 - 160 KIAS

VR - Generalized Rotation Speed: 180 (minimum) - 220 KIAS

V2 - Generalized Engine Failure Screen Speed:
190 - 220 KIAS

Take Off Speed (MLW):
220 KIAS (+10 deg pitch)
200 KIAS 22% COG 58,600 lbs fuel.
180 KIAS 45K lbs fuel.

---- LANDING ----
Normal Landing Weight:
10,000 lbs fuel or less
Minimum Landing weight:
5,000 lbs fuel
Max T&G - Touch and Go weight:
22,000 lbs fuel
MLW - Maximum Landing Weight:
215,000 lbs (40,000 lbs fuel)
Note: AP GS track is very unstable at this weight.

VREF - Target Landing Speed (KIAS):
Fuel lbs Appr Spd TD Spd
<= 10K 175 155
20K 185 165
25K 190 170
30K 195 175
40K 205 185

Landing Threshold Angle of Attack:
9.5 degrees (Att Ind pitch.)
10.5 AOA
Max Threshold AOA:
+14 (tail strike)
Max Maneuver AOA:
+8 on turns (225 KIAS) +9 on final.

Max Landing Sink Rate:
8 FPM

Touchdown Throttle Setting:
Idle

Landing Crosswind Limit:
35 Knots @ 90 degrees

Drag Chute: activatedon the ground with "shift-/" (spoiler arm keypress.)
Pre-arm: shft-/
Flight not possible while activated.
Max Chute Deploy Angle:
10 deg
Max Chute Deploy Speed:
210 KIAS
Chute Deploy Timing:
On Mains Contact
Chute Deploy Time:
5 seconds
Chute Deploy force:
0.5G

No Power Glide (80K ft Mach 3.2):
375KIAS @ -11,600 ft/min
6 minutes to 10Kft (102nm)

Dipsey Doodle (modified for FS9/FSX):
After refueling, set AT hold for speed Mach .9, engage AB and set climb rate to 2000 ft/min. Between 30K-32K ft increase AT speed bug to 405. Passing M0.95 and 32Kft set AT bug for 440 and reduce climb to 500ft/min.
When passing M1.05. slowly increase climb to +1500 until M1.15 then increase climb to desired rate using 400 KEAS or 450 KEAS.

Real world tanker descent (assumes M3.2 80Kft):
After starting descent, switch to KIAS Hold and slow gradually until crossing KEAS and click KEAS Hold.
Tanker is expected 100 miles this side of runway.
-Set descent alt (target) in AP for tanker alt.
-Gradually set initial dec rate to 4500, Mach 3.2.
-Crossing -2500 ft/min on VSI disengage AB.
-Follow published descent profile for alt and distance to target.
-Typical descent rates are -4500 to -6200 ft/min.
-Below Mach 1.50 maintain 400 KIAS.

Typical Descent Target Profile:
Land/Refuel
Distance:
Alt: Spd:
395/308 90Kft M3.2/365 KEAS
325/238 80K M3.2/365 "
282/190 74K 365+ KEAS
264/170 70K 365
220/116 60K 365
190/70 50K 365
163/40 40K 400 KIAS
150/00 35K 380 KIAS, M0.90 cruise, or M0.85 for tanker

--- If using tanker, start rendezvous operations. ----
-Typical landing final approaches start 20 miles out 4,000 ft above runway altitude.

Re-Fuel Constraints:
o 270 - 350 KIAS
o 24K ft - 36K ft
Both engine fuel valves must be enabled (engines are operating normally.)

NOTE: For explanations of speeds used on this tab, see "V-speeds" in the Glossary section of Help.

NOTE: This aircraft's real-world checklists have been modified
for use with Flight Simulator. To learn about using, printing,
and customizing checklists: in the
"Getting From Here to There" section of Simulator Help,
click "Using the Kneeboard."