Fam 1 Flashcards
VRS is what?
When a helo can have max power applied, but still be in a descent with little or no cyclic authority
Because helo os descending into and recirculating its own downwash
Vortices use engine power and do not produce lift, so accelerating the vortices diminish rotor efficiency
When is VRS measureable?
700 fpm descents at 0-20 KIAS
When is VRS at it’s worst?
1500 fpm descents at 5-10 KIAS
What are indications of a fully developed VRS?
- uncommanded pitch and roll oscillations
- little or no cyclic authority
- descent rate that may approach 6000 fpm
- increased levels of vibration
How do you recover from VRS?
- Decrease collective
- Increase fwd airspeed (cyclic fwd)
- Enter automation (if altitude permits or ina fully developed VRS)
considerable amount of altitude loss may occur before condition recognized and recovery complete. Avoid this during approaches!!!
VRS warning
- flight conditions causing VRS should be avoided at low altitudes because of loss of altitude required to recover
- recovery from fully developed VRS may require entering auto before regaining airspeed
VRS note/advisory
- VRS may be entered during any dynamic maneuver that places the main rotor in a condition of high upflow and low longitudinal airspeed
- thisbconditioj is frequently seen during “quick stop” type maneuvers or during autorotational recoveries
When does tail rotor VRS occur?
210-330° winds
Causes tail rotor to re-circulate its own airflow and thus LTE (loss of tail rotor effectiveness) occurs
T/r VRS causes
Variations in t/r thrust, which can initiate yaw rates, which can increase workload in directional control
If a RIGHT yaw rate is allowed to build l, the tail can get caught in the weather-vaning region causing thr aircraft to “whip” or rapidly yaw into the wind
How to respond to LTE:
- Lower collective (altitude permiting) (to reduce Q and arrest right yaw)
- Increase airspeed (fwd cyclic and if necessary turn in thr direction of rotation) (this results in a reduction of t/r thrust required and produces a streamlining effect)
- At low airspeed or in a hover, FULL LEFT PEDAL (may arrest yaw rate, may take a few secs to take effect….neutralizing pedals or adding right pedal or increasing collective will accelerate the yaw rate)
HV diagrams
Aka Deadman’s curve
Dependent on environmental and aircraft engine conditions
Based on average pilot’s reaction time to recognize and then enter auto
Abort Start
Abort engine start if any if the following limits are exceeded:
- Ng does not reach 14% within 6 seconds after starter initiation
- No oil px within 30 seconds after starter initiation ( do NOT motor engine)
- No light-off within 30 secs after moving PCL to IDLE
- Engine starter advisory disappears before reaching 52% Ng
- TGT likely to exceed 851°C before idle speed is reached
TO ABORT START:
- PCL - OFF
- ENGINE IGNITION - OFF
IF ENGINE OIL PX IS INICATED:
3. STARTER-ENGAGE
CAUTION: during aborted starts failure to immediately stop fuel flow may result in engine over temperature
Immediate landing/ditching (pilot)
- Crew and passengers - alert
- Shoulder harness - locked
- External cargo/stores/fuel - jettison/dump, as req
- Searchlight - as req
- Mayday/iff - transmit/emergency
In the flare:
6. Windows - jettison, as req
After landing:
- Pcls - off
- Roto brake - on
- Copilot collective - stow
- Pilot hcu - stow
After all violent motion stops:
11. Egress
WARNING: stores jettisoned at descent rates greater than those listed in NATIP have not been tested. Aircraft/rotor system impact from jettisoned stores may be possible
CAUTION: time permitting, consideration should be given to executing APU emergency start procedure to maintain electrical and hydraulic power upon rotor disengagement
WARNING: after actuation, the position of emergency jettison window lever may cause snagging of personal survival gear, impending egress. Time, permitting, reset jettison handle to aft position prior to egress
WARNING: failure to remain strapped in aircraft until all violent motion or in-rushing water stops may result in injury or incapacitating
Underwater egress
- Emergency breathing device - as req
- Cord(s) - disconnect
- Door/window - open/jettison
- Place hand on known reference point
- Harness - release
- Exit helicopter
After egress:
7. Swim clear of helicopter and inflate LPU
WARNING: the dowmward stroke of the seat will change thr frame of reference needed for egress. Extended handles, windows, and controls will not be located in the same relative position. Keep legs clear from under seat area. Downward travel of seat may cause injury or entrapment
WARNING: do not inflate LPU until outside helicopter
WARNING: water px may prevent opening the emergency egress windows until the cabin fills with water. The windows should be jettisoned prior to water entry to optimize the ability if the crew to safely egress
WARNING: failure to disconnect ICS cord can impede egress. Personal gear may snag during egress, notably on collectives, FLIR HCUs, parking brake and RAST release handles, PCLs/ fuel selectors, fire t-handles, or extended emergency jettison window handles
WARNING: if entanglement or disorientation delays egress, hold onto a reference point with one hand. Using the other hand, place emergency breathing device in your mouth, clear water from your mouthpiece, and continue with egress
Where can you enter rotor arc?
3 or 9 o’clock positions
Do NOT go aft of IRCM dispensers while rotors turning
