Measured Loads Component Strength Usage (Flight Load Survey) (S/N Curve) (Flight Spectrum) Miner's Rule Life Determination FIGURE AC 27.MG 11-6: Elements of Safe-Life Determination AC Page MG 11 - 19
AC 27-1B, Chg 1 2/12/03 FIGURE AC 27.MG 11-7
FLIGHT LOAD MEASUREMENT PROGRAM CONDITIONS TO BE INVESTIGATED
1. GROUND CONDITIONS.
a. Normal start.
b. Rapid increases of RPM on ground to maximum power-on RPM of main rotor.
c. Taxiing with max allowable full cyclic control.
d. Landing run (if applicable).
e. Braking (if applicable).
f. Normal shutdown.
g. Special ground checks (if applicable).
2. HOVERING IN AND OUT (1) Steady with rotor at OF GROUND-EFFECT maximum side of RPM tolerance.
(2) Steady with rotor at minimum side of RPM tolerance.
(3) 90-degree right turn
(4) 90-degree left turn
(5) Control reversals
i) Longitudinal.
ii) Lateral.
ili) Rudder.
(6) Sideward flight
i) Left.
ii) Right.
(7) Rearward flight
3. MANEUVERING IN (1) Jump takeoff.
GROUND EFFECT (2) Normal takeoff (*) and accelerate to climb airspeed.
(4) Full autorotational landing. (3) Normal Landing (*) i) Multiengine. ii) One-engine-inoperative.
Page MG 11 - 20
FIGURE AC 27.MG 11-7 (continued)
4. FORWARD FLIGHT-POWER (1) 40 percent VH i) Minimum side of main rotor ON. RPM tolerance (RPM -)
a. Level flight. (**) ii) Maximum side of main rotor RPM tolerance (RPM +)
(2) 60 percent VH i) (RPM +) ii) (RPM -)
(3) 80 percent VH i) (RPM +) ii) (RPM -)
(4) VH i) (RPM +) ii) (RPM -)
(5) VNE i) (RPM +) ii) (RPM -)
b. Maneuvers. (1) Full power climbs. (**) i) All engines operative.
ii) One-engine-inoperative.
(2) Cyclic pull-ups. i) 60 percent VH.
ii) 90 percent VH.
(3) Normal acceleration from climb airspeed to 90 percent VH.
(4) Turns, right and left over a range of bank angles and speeds up to the lesser of VH or VNE and including:
i) Right at 60 percent VH and 90 percent VH.
ii) Left at 60 percent VH and 90 percent VH.
(5) Control reversals at 90 percent
i) Longitudinal.
ii) Lateral.
iii) Rudder.
(6) Deceleration from 90 percent Vu to descent airspeed.
(1) Partial power descent. (*)
(2) Normal approach
(3) Steep Approaches (to landing) i) All engines.
or Flare FIGURE AC 27.MG 11-7 ii) One engine out.
AC Page MG 11 - 21
AC 27-1B, Chg 1 2/12/03 (continued)
5. POWER TRANSITIONS.
a. All engines operating to one (1) In full power climb.
engine out. (2) At 90 percent VH.
b. One engine out to all engines operating in powered descent.
c. All engines operating to (1) At 60 percent VH.
autorotation. (2) At maximum forward transition speed.
d. Stabilized autorotation to all engines operating at normal autorotation airspeed.
6. AUTOROTATION.
a. Stabilized. (1) At 70 percent VNE•
(2) At VNE•
b. Turns at 70 percent and 100 (1) Right.
percent VNE• (2) Left.
c. Cyclic pull-up.
d. Control reversals. (1) Longitudinal.
(2) Lateral.
(3) Rudder.
(**) side slip conditions should be considered (*) max slope angle and aircraft headings should be considered Page MG 11 - 22
FIGURE AC 27.MG 11-8
LIFTING HELICOPTER LOAD MEASUREMENT in addition to normal conditions CONDITION %RATED LOAD % VNE
ROTOR START VERTICAL LIFT 100 87 HOVER including spot turns 100 sideward and rearward flight and control reversal.
87 CRUISE with load 100 100 87 100 100 90 87 90 CRUISE no load 100 90 CLIMB max. rate DECELERATIONS max. rate
GROUND IDLE
SHUTDOWN AC Page MG 11 - 23
AC 27-1B, Chg 1 2/12/03 FIGURE AC 27.MG 11-9. EXAMPLE OF TWIN TURBINE USAGE SPECTRUM Notes:
1. Altitude, temperature, center of gravity, and weight variations may be appropriate where justified by service data; otherwise the worst case must be assumed throughout.
This spectrum is an example only; all probable types of operation must be accounted for unless prohibited--see Section 3.
CONDITION o of time No per hour ON GROUND inc START UP 3.5 5 TAXIING 3.5 APPROACH 2 NORMAL 3.5 UNDER HEAVY SLOPE 0.75 FLARE 0.375 QUICK-STOP 0.375 Dur. 14 (s)
SPOT-TURN 30°/S/NORM (STOP)/RIGHT 0.32 1.6 Yaw speed rep. Stop rep.
30°/S/NORM (STOP)/LEFT 0.32 1.6 80.00% 30° 80.00% normal 30°/S/MAX (STOP)/RIGHT 0.08 0.4 15.00% 45° 20.00% max 30/S/MAX (STOP)/LEFT 0.08 0.4 5.00% max 45°/S/NORM (STOP)/RIGHT 0.06 0.3 45°/S/NORM (STOP)/LEFT 0.06 0.3 45°/S/MAX (STOP)/RIGHT 0.015 0.075 45°/S/MAX (STOP)/LEFT 0.015 0.075 MAX/NORM (STOP)/RIGHT 0.02 0.1 MAX/NORM(STOP)/LEFT 0.02 0.1 MAX/MAX (STOP)/RIGHT 0.005 0.025 MAX/MAX (STOP)/LEFT 0.005 0.025 Dur. 7.2 (s) LANDING 1.5 NORMAL 1.482 5.94 1/20 hours slope 8° ON SLOPE/8DEG/RIGHT 0.0043 0.0145 1/100 hours slope 10° ON SLOPE/8DEG/LEFT 0.0043 0.0145 8DEG/NOSE-UP 0.0038 0.0125 8DEG/NOVE-DOWN 0.0043 0.0145 ON SLOPE/10DEG/NOSE-UP 0.0006 0.002 COMB.SLOPE 0.0006 0.002 Dur. 11 (s) AUTOROTATION Speed rep RPM rep.
VERTICAL 0.05 0.05 5.00% 70Kts 10.00% Mini 40 KTS 0.2 0.2 20.00% 70Kts 50.00% Nomi 70 KTS 0.3 0.3 30.00% 70Kts 36.00% Maxi 120 KTS 0.25 25.00% 120Kts 4.00% Maxi.trans 135 KTS 0.15 0.15 15.00% 135Kts VNE 0.05 0.05 5.00% VNE Dur. 36 (s) TAKE OFF 1.5 5 Dur. 11 (s) NORMAL 0.8892 2.964 60.00% Normal QUICK 0.5928 1.976 40.00% Quick ON SLOPE/8DEG/RIGHT 0.0043 0.0145 1/20 hours slope 8° ON SLOPE/8DEG/LEFT 0.0043 0.0145 1/100 hours slope 10° ON SLOPE/8DEG/NOSE-UP 0.0038 0.0125 ON SLOPE/8DEG/NOVE-DOWN 0.0043 0.0145 ON SLOPE/10DEG/NOSE-UP 0.0006 0.002 COMB.SLOPE 0.0006 0.002 DESCENT 1.5 2 PARTIAL POWER/STD/STD 0.96 1.28 Speed rep. Side slip PP values rep.
PARTIAL POWER/5 DEG/RIGHT 0.072 0.096 80.00% Partial power 60.00% 5° PARTIAL POWER/5 DEG/LEFT 0.072 0.096 20.00% VNE 30.00% 10° PARTIAL POWER/10 DEG/RIGHT 0.036 0.048 8.00% 15° PARTIAL POWER/10 DEG/LEFT 0.036 0.048 Side slip rep. 2.00% 20° PARTIAL POWER/15 DEG/RIGHT 0.0096 0.0128 80.00% Without PARTIAL POWER/15 DEG/LEFT 0.0096 0.0128 20.00% with Side slip VNE values rep.
PARTIAL POWER/20 DEG/RIGHT 0.0024 0.0032 90.00% 5° PARTIAL POWER/20 DEG/LEFT 0.0024 0.0032 10.00% 10° VNE AT MCP/STD/STD 0.24 0.32 VNE AT MCP/5 DEG/RIGHT 0.027 0.036 VNE AT MCP/5 DEG/LEFT 0.027 0.036 VNE AT MCP/10 DEG/RIGHT 0.003 0.004 VNE AT MCP/10 DEG/LEFT 0.003 0.004 Page MG 11 - 24
FIGURE AC 27.MG 11-9. EXAMPLE OF TWIN TURBINE USAGE SPECTRUM (continued) CONDITION % of time Nb per hour CLIMB 4 MCP 75 KTS/STD/STD 1.8 2.4 Climb rep. Side slip values rep.
MCP 75 KTS/05-10 DEG/RIGHT 0.18 0.24 75.00% 75 Kts 80.00% 05 10 MCP 75 KTS/05-10 DEG/LEFT 0.18 0.24 25.00% Vertical 18.00% 15 20 MCP 75 KTS/15-20 DEG/RIGHT 0.0405 0.054 2.00% 25 30 MCP 75 KTS/15-20 DEG/LEFT 0.0405 0.054 MCP 75 KTS/25-30 DEG/RIGHT 0.0045 0.006 Side slip rep.
MCP 75 KTS/25-30 DEG/LEFT 0.0045 0.006 80.00% Without TOP/VERTICAL 0.75 1 20.00% with Dur. 27 (s) LEVEL FLIGHT 56.5 80% MCP/STD/STD 12.4 Speed rep. Side slip rep.
80% MCP/5 DEG/RIGHT 1.08 28.3% 80% MCP 80.00% Without 80% MCP/5 DEG/LEFT 1.08 36.3% 90% MCP 20.00% with 80% MCP/10 DEG/RIGHT 0.54 35.4% MCP 80% MCP/10 DEG/LEFT 0.54 80% MCP/15 DEG/RIGHT 0.144 80% MCP/15 DEG/LEFT 0.144 Side slip typ rep.
80% MCP/20 DEG/RIGHT 0.036 60.00% 5° 80% MCP/20 DEG/LEFT 0.036 30.00% 10° 90% MCP/STD/STD 16.3 8.00% 15° 90% MCP/5 DEG/RIGHT 1.26 2.00% 20° 90% MCP/5 DEG/LEFT 1.26 90% MCP/10 DEG/RIGHT 0.63 90% MCP/10 DEG/LEFT 0.63 90% MCP/15 DEG/RIGHT 0.21 90% MCP/15 DEG/LEFT
MCP/STD/STD MCP/5 DEG/RIGHT MCP/5 DEG/LEFT 0.9 MCP/10 DEG/RIGHT 0.45 MCP/10 DEG/LEFT 0.45 MCP/15 DEG/RIGHT 0.15 MCP/15 DEG/LEFT 0.15 PULL-UP 0.22 1.1 PULL-UP/VNE 0.01 0.05 PULL-UP/LEVEL FLIGHT 80%MCP 0.1 0.5 PULL-UP/LEVEL FLIGHT 90%MCP 0.1 0.5 PULL-UP/AUTOROTATION 0.01 0.05 Dur. 7.2 (s) HOVERING 10 10 HOVERING/IGE 9
HOVERING/OGE Dur. 36 (s) TRANSITION 4.52 19.6 TRANSITION/CLIMB TO VMAX 0.292 5 RANSITION/90 MCP TO V.DESC(ISO-V) 0.292 'RANSITION/ 'O AUTO. (65 KTS) 0.292
0.06 O FWD FLIGHT 3 Dur. 22 (s)
0.292 TRANSIT SE(65 KTS) 0.292 Dur. 3.6 (s) AC Page MG 11 - 25
AC 27-1B, Chg 1 2/12/03 FIGURE AC 27.MG 11-9. EXAMPLE OF TWIN TURBINE USAGE SPECTRUM (continued) CONDITION % of time Nb per hour TURNS 30 TURNS/60% MCP/NZ 1.2G/RIGHT 0.2667 Speed rep. Nz rep TURNS/60% MCP/NZ 1.2G/LEFT 0.2667 10.00% 60% MCP 10 > 1.2g TURNS/60% MCP/NZ 1.4G/RIGHT 0.0989 0.3709 30.00% 80% MCP 20 1.2g TURNS/60% MCP/NZ 1.4G/LEFT 0.0989 0.3709 35.00% 90% MCP TURNS/60% MCP/NZ 1.6G/RIGHT 0.0330 0.1237 25.00% MCP TURNS/60% MCP/NZ 1.6G/LEFT 0.0330 0.1237 TURNS/60% MCP/NZ 1.8G/RIGHT 0.0013 0.005 Nb per hour TURNS/60% MCP/NZ 1.8G/LEFT 0.0013 0.005 20 1.2g 1.4/1.6g rep.
TURNS/60% MCP/V.LIM +0.1G/RIGHT 0.00013 0.0005 7.4175 1.4g 75.00% 1.4g IURNS/60% MCP/V.LIM +0.1G/LEFT 0.00013 0.0005 2.4725 1.6g 25.00% 1.6g TURNS/80% MCP/NZ 1.2G/RIGHT 0.8 0.1 1.8g TURNS/80% MCP/NZ 1.2G/LEFT 0.8 3 0.01 V.limt0.1G TURNS/80% MCP/NZ 1.4G/RIGHT 0.2967 1.1126 URNS/80% MCP/NZ 1.4G/LEFT 0.2967 1.1126 TURNS/80% MCP/NZ 1.6G/RIGHT 0.0989 0.3709 TURNS/80% MCP/NZ 1.6G/LEFT 0.0989 0.3709 TURNS/80% MCP/NZ 1.8G/RIGHT 0.004 0.015 TURNS/80% MCP/NZ 1.8G/LEFT 0.004 0.015 TURNS/80% MCP/V. LIM +0.1G/RIGHT 0.0004 0.0015 TURNS/80% MCP/V.LIM +0.1G/LEFT 0.0004 0.0015 TURNS/90% MCP/NZ 1.2G/RIGHT 0.9333 3.5 TURNS/90% MCP/NZ 1.2G/LEFT 0.9333 3.5 TURNS/90% MCP/NZ 1.4G/RIGHT 0.3461 1.298 TURNS/90% MCP/NZ 1.4G/LEFT 0.3461 1.298 TURNS/90% MCP/NZ 1.6G/RIGHT 0.1154 0.4327 TURNS/90% MCP/NZ 1.6G/LEFT 0.1154 0.4327 TURNS/90% MCP/NZ 1.8G/RIGHT 0.0046 0.0175 TURNS/90% MCP/NZ 1.8G/LEFT 0.0046 0.0175 TURNS/90% MCP/V.LIM +0.1G/RIGHT 0.0004 0.00175 TURNS/90% MCP/V.LIM +0.1G/LEFT 0.0004 0.00175 TURNS/MCP/NZ 1.2G/RIGHT 0.6667 2.5 TURNS/MCP/NZ 1.2G/LEFT 0.6667 2.5 TURNS/MCP/NZ 1.4G/RIGHT 0.2473 0.9272 TURNS/MCP/NZ 1.4G/LEFT 0.2473 0.9272 TURNS/MCP/NZ 1.6G/RIGHT 0.0824 0.3091 TURNS/MCP/NZ 1.6G/LEFT 0.0824 0.3091 TURNS/MCP/NZ 1.8G/RIGHT 0.0033 0.0125 TURNS/MCP/NZ 1.8G/LEFT 0.0033 0.0125 TURNS/MCP/V.LIM +0.1G/RIGHT 0.0003 0.0013 TURNS/MCP/V.LIM +0.1G/LEFT 0.0003 0.0013 Dur. 9.6 (s) SPECIAL TURNS 0.76 2.025 TURNS/VNE(30DEG)/*/RIGHT 0.0038 0.01 TURNS/VNE(30DEG)/*/LEFT 0.0038 0.01 TURNS/VNE IN AUTO. (30DEG)/*/RIGHT 0.00094 0.0025 TURNS/VNE IN AUTO. (30DEG)/*/LEFT 0.00094 0.0025 TRANSITION/TURN IN TRANSITION/*/RIGHT 0.3753 1 TRANSITION/TURN IN TRANSITION/*/LEFT 0.3753 Dur. 14 (s) Page MG 11 - 26
FIGURE AC 27.MG 11-9. EXAMPLE OF TWIN TURBINE USAGE SPECTRUM (continued) CONDITION % of time Nb per hour LATERAL FLIGHT Dur. 9 (s) 5 KTS/*/RIGHT 0.095 0.38 Lat.Back rep. Speed rep.
5 KTS/*/LEFT 0.095 0.38 95.00% Lateral 10.00% 5 kts 10 KTS/*/RIGHT 0.095 0.38 5.00% Backward 10.00% 10 kts 10 KTS/*/LEFT 0.095 0.38 10.00% 15 kts 15 KTS/*/RIGHT 0.095 0.38 40.00% 17 kts 15 KTS/*/LEFT 0.095 0.38 10.00% 19 kts 17 KTS/*/RIGHT 0.38 1.52 5.00% 21 kts 17 KTS/*/LEFT 0.38 1.52 5.00% 25 kts 19 KTS/*/RIGHT 0.095 0.38 5.00% 35 kts 19 KTS/*/LEFT 0.095 0.38 5.00% max 21 KTS/*/RIGHT 0.0475 0.19 21 KTS/*/LEFT 0.0475 0.19 25 KTS/*/RIGHT 0.0475 0.19 25 KTS/*/LEFT 0.0475 0.19 35 KTS/*/RIGHT 0.0475 0.19 35 KTS/*/LEFT 0.0475 0.19 VMAX/*/RIGHT 0.0475 0.19 CONDITION % of time Nb per hour VMAx/*/LEFT 0.0475 0.19 VMAX/*/REARWARD 0.1 0.4 100 AC Page MG 11 - 27
AC 27-1B, Chg 1 2/12/03
INTENTIONALLY LEFT BLANK Page MG 11 - 28
CHAPTER 3
AIRWORTHINESS STANDARDS
NORMAL CATEGORY ROTORCRAFT
MISCELLANEOUS GUIDANCE (MG) AC 27 MG 12. § 27.865 (Amendment 27-36) EXTERNAL LOADS.
This AC MG paragraph material is now contained in AC 27.865B, in Subpart D.
Page MG 12 - 1
AC 27-1B, Chg 1 2/12/03 Page MG 12 - 2