Limits Flashcards
Engines are limited by…
Ng, Np, TGT, oil pressure, oil temperature
Anytime an operational limit is exceeded…
An appropriate entry shall be made on a MAF. The entry shall state what limit(s) were exceeded and include range, duration, and any additional data that would aid maintenance personnel.
Note: If a limit is exceeded to the extent that a red “XXX” is indicated, the crew shall land as soon as practicable.
Start cycle definition
Starter initiation, acceleration in Ng, and starter dropout/disengagement. A 60-second delay between start attempts is required any time a start is aborted, except during emergencies.
Crossbleed starts
May be attempted with the operating engine at or above 94% Ng and rotor speed at 100% Nr. Engine starts with the main rotor blades and/or tail rotor pylon folded are prohibited.
Caution: Donor of Ng less than 94 percent may result in hot starts.
DECU TGT Limits (IRP)
0-810: continuous: green
>810-851: 30 mins: yellow
>851-903: 2.5 mins: Red
>903-949: 12 secs: Red
EDECU TGT Limits (MRP)
0-810: continuous: green
>810-851: 30 mins: yellow
>851-878: 10 mins: yellow
>878-903: 2.5 mins: Red
>903-949: 12 secs: Red
949: Max: RedNp Limits
> 96%: Avoid: Red
96-101%: Cont: Green
101-120%:12 sec:Yellow
120%: Max: Red
Caution: Operating engine steady state between 20 to 40% Np or 60 to 75% Np may cause engine damage.
Nr limits
<96%: Avoid: Red
96-101%: Cont: Green
101-120%: P: Yellow
120%: Max: Red
127, 137, 142: OL: RedDual-Engine Q <80 KIAS
0-120%: Cont: Green
120-144%:10 s: Yellow
144%: Max: Red
Dual-Engine Q >80 KIAS
0-106%: Cont: Green
106-127%%:10 s: Yellow
127%: Max: Red
Single-Engine Q
0-135%: Cont: Green
135-144%:10 s: Yellow
144%: Max: Red
Ng Limits
0-98%: Cont: Green
98-102%: Cont: Yellow
102-105%:12 sec: Red
105%: Max: Red
XMSN Temperature
-50-105: Cont: Green
105-120: P :Yellow
120: Max : Red
XMSN Pressure
<20: Min: Red 20-30: Idle and transient: Yellow 30-65 (45-60 in lvl flt): Cont: Green 65-130: P: Yellow 130: Max: Red
Engine Oil Temp
-50-135: Cont: Green
135-150: 30 mins: Yellow
150: Max: Red
Engine Oil Pressure
22: Min: Red 22-26: P: Yellow 26-100: Cont: Green 100-120: P: Yellow 120: Max: Red Note: Normal idle range is 22 to 55 psi.
Engine Starter Limits
Engine Start:
<16: 60-60-60-30 mins
16-52: 60-30 mins
Engine Motoring:
Any temp: 2 mins-5mins-2 mins-30 mins
Engine operation with…
the gust lock engaged is prohibited
Minimum Planned Fuel on Landing
Shall be no less than 225 lbs (approximately 20 mins) of fuel per main tank. With fuel less than 300 lbs per main tank, maintain balanced flight at AOBs greater than 30 degrees.
APU Limits
The APU is not intended for routine in-flight use. Operation of the APU in flight shall be limited to essential operations only. Acceptable in-flight use includes EPs, single engine training, practice autorotations, and powering the ECS during extreme temperature operations.
Transmission is limited by:
Nr, torque, oil pressure, and oil temperature
Note: Prolonged hovering in hot weather 95 degrees and high gross weight may cause temperatures to rise in the yellow precautionary range. Operations in the precautionary range for less than 30 mins durning any one flight under these conditions is acceptable.
Transmission Oil Pressure Limitations
During steady-state level pitch attitudes xmsn pressure should be between 45-60.
The following conditions do not constitute an immediate emergency situation, but may be indicative of a degraded lubrication system. Maintenance action shall be performed to prevent potential long-term damage to the gear box:
- Steady state pressure outside of 45-60 but w/in normal 30-65.
- Flux not to exceed a range of 10 psi within normal 30-65.
During transient pitch or steady-state nose-high pitch attitudes xmsn oil press flux (including momentary flux below 30 psi and transient drops below 20 psi for up to 1 sec) are acceptable. Press flux below 30 psi shall be limited to 30 mins
Max Wind Velocity for rotor engagement or disengagement
45 kts from any direction
Airspeeds
Auto: 100 KIAS Sideward/Rearward flight: 45 KIAS (35 with an external load) Two sas inop in IMC- 125 KIAS SAS/Boost Off- 140 KIAS Either PRI SERVO PRESS caution- 125 KIAS Cabin doors open- 120 KIAS Cabin doors open/closing- 100 KIAS Gunner windows opening/closing- 170 KIAS Landing light in transition- 130 KIAS Searchlight in transition- 100 KIAS Aircraft gross weight >22,000 lbs with an external load- 120 KIAS
Maneuvering with Rescue Hoist Loads rate of descent
1000 fpm
Hovering Limits
- Prolonged rearward flight and downwind hovering should be avoided to prevent accumulation of exhaust fumes in the helicopter and heat damage to window on open cabin doors
- Hovering turns at a rate in excess of 30 degrees per second.
Max AOB with an external load
30 degrees in forward flight
- 20- 20 degrees
- 30- 0 degrees
AOB limits
Normal operations: 45 degrees
Operations above 10,000 DA: 30 degrees
Either PRI SERVO PRESS caution on: 30 degrees
SAS/BOOST OFF flight: 30 degrees
Max Operating Density Altitude
13,000 feet
Prohibited Manuevers
- Aerobatic flight.
- Practice full-autorotation landings.
- Intentional approaches into or inducement of retreating blade stall.
Rotor Brake Operating Limits
Max rotor speed for rotor brake application: 76 percent Nr
Routine rotor stops shall be made between 30 and 50 percent Nr. Routine rotor brake stops should be limited to 180 psi to extend service life.
Blade, Pylon, and Stab Fold and Spread Limits
Max wind velocity for blade fold and spread: 45 kts from any direction
Following a complete blade fold and spread cycle, allow a 10-min cooling period before commencing another blade fold and spread evolution.
Max wind velocity for tail pylon or stab fold/spread operations is 45 kts from any direction.
Landing Limits
- Max ROD for level terrain shall not exceed 540 fpm.
- Max ROD for sloped terrain shall not exceed 360 fpm.
- Max touchdown and takeoff speed shall not exceed 60 KGS with tailwheel locked and 20 KGS with tailwheel unlocked.
- Max braking speed is 35 KGS.
- Slope landing limits: 9 degrees nose up/12 cross slope/6 nose up
- Downwind landings should be avoided.
Window Limits
Windows shall not be installed or removed in flight, except during actual aircraft emergencies.
Aircraft Operating Gross Weight Limitations
Max operating gross weight: 23,500
Aviation ships: 23,500
Air-capable ships: 22,500
Internal Load Weight Limits
Total Internal Weight in the cabin aft of the cockpit: 5, 500 lbs
Max weight for palletized cargo is 4,733 lbs
Max weight for a single pallet of cargo is 3,000 lbs
External Load Weight Limitations
Max external load when employing the cargo hook: 8,000 lbs
Max load when employing the rescue hoist: 600 lbs
Min Aircraft Equipment for Night Flight over Water
LAWS
Altitude Hold
Min Equipment for Flights into Forecast or Known Icing Conditions
All installed anti-ice equipment (windshield, engine, rotor) shall be operational prior to flight.
Blade Deice not Installed
Helicopters not equipped with operable blade deice equipment are prohibited from flight into forecast or known icing conditions (ambient temperature of 5 degrees or blow in visible moisture).
Helos Equipped with Operable Anti-ice/Deice
Helos equipped with operable anti-ice and blade deice equipment are permitted flight into forecast or known trace or light icing conditions.
Warning: Flight into forecast or known moderate or severe icing conditions is prohibited.
Helo Emergency Egress Lighting
Except in in emergency situations, helicopter emergency egress lighting system (ADHEELS and IHEELS) shall be operational for all overwater flights requiring passengers/non-aircrew in the cabin.
Temperature Limitations
Operations at temperatures below -40 deg C (-40 deg F) or above 60 deg C (140 deg F) are prohibited.
Backup Hyd Pump Limits
Rotor System Static:
33-38 deg: 24 oper: 72 cool
39-60 deg: 16 oper: 48 cool
APU Operating Limits
Rotors not engaged: APU may be operated continuously up to an ambient temperature limit of 51 deg C.
Rotors engaged: APU may be operated continuously up to an ambient temp of 43 deg C. If operating the APU between 43 and 60 deg C, operating is limited to 30 mins.
Caution: Exceeding time or ambient temperature limits may cause APU overheating, performance degradation, and a reduction in APU reliability.
