Daily Questions Contact Flashcards
What are the definitions of “WARNINGS” CAUTIONS” and “NOTES” inthe operator’s manual?
An operating procedure, practice, condition or
statement, which if not correctly followed, could
result in personal injury or loss of life.
An operating procedure, practice, etc., which if
not strictly observed, could result in damage to
or destruction of equipment.
An operating procedure, condition, etc., which
is essential to highlight.
Where does the APU get its fuel?
The APU receives fuel from the left main fuel tank through a booster pump, a manual fuel shutoff valve, and two solenoid valves. The APU fuel burn rate is approximately 90 PPH.
Where is the APU ESU located and what does it do?
The ESU/DESU is mounted on the left side of the cabin above the ramp (Figure 2-61). The unit monitors APU starting and operation. The unit continuously compares APU speed and exhaust gas temperature with limits programmed into the ESU/DESU circuits. If a limit is exceeded, the ESU/DESU will automatically shut down the APU.
What is the difference between angle-of-incidence and angle-of-attack?
Angle of incidence is a “mechanical angle” and AOA is an “aerodynamic angle””
How is dissymmetry-of-lift compensated for in a tandem rotor helicopter with a fully articulated rotor system?
In tandem-rotor helicopters, the aviator does not manually compensate for dissymmetry of lift whenapplying forward cyclic. Automatic cyclic-feathering systems are installed on tandem-rotor helicopters. Thesesystems are activated through computer-generated commands at specified airspeeds, usually starting around 70knots.
At low airspeeds, blade flapping compensates for dissymmetry of lift. As airspeed increases, these systems program allowing a more level fuselage attitude and reduce stresses on the rotor driving mechanisms.
During run-up, prior to engine start, how are the flight control hydraulics pressurized?
Utility power system (pressurized by the APU motor pump) provides pressure to the flight controls through the PTUs
Below what pressure altitude will the engine driven fuel pumps draw fuel from the main tanks if both main fuel pumps fail?
6,000 ft PA
What is the emergency procedure for an ENG1 FUEL PRESS LO or ENG2 FUEL PRESS LO Caution?
Immediate Actions:
1. XFEED Switch — OPEN (above 6,000
feet PA).
Subsequent Actions:
1. FUEL PUMP(S) Circuit Breakers — Check
in.
Pump(s) are operational:
2. XFEED Switch — CLOSE.
Pump(s) are not operational:
3. FUEL PUMP Switch(es) (inoperative
pump(s)). — OFF.
- Failure of main tank fuel boost pumps with
the crossfeed open and a fuel low condition
may result in a dual engine flameout. - Nose low attitudes should be avoided.
- Nose low attitudes in excess of 5° may cause
fuel starvation prior to the fuel low caution
activating.
What is the emergency procedure for L FUEL LVL and ENG2 FUEL PRESS LO Caution?
Immediate Actions:
1. XFEED switch — CLOSE.
Urgency to Land:
LAND AS SOON AS POSSIBLE
Failure of main tank fuel boost pumps with
the crossfeed open and a fuel low condition
may result in a dual engine flameout.
* Nose low attitudes should be avoided.
* Nose low attitudes in excess of 5° may cause
fuel starvation prior to the fuel low caution
activating.
Explain GO/NO GO Torque.
The GO/NO-GO TQ value, calculated at the desired HVR altitude, is proportional to the MAX TQ AVAIL (10-minute limit) at OGE. That is, if the GO/NO-GO TQ is exceeded at the desired HVR altitude, then MAX TQ AVAIL (10-minute limit) will be exceeded if OGE maneuvers are attempted. OGE maneuvers should not be attempted if GO/NO-GO TQ is exceeded.
Explain Validation Factor.
Validation factor is a TQ value that is equal to your MAX allowable GWT for your mission profile based on departure conditions. If this value is exceeded prior to obtaining a desired wheel height HVR altitude then the aircraft GWT must be adjusted (unload cargo, passengers, or fuel) to ensure the aircraft is kept within the current operator’s manual limitations.
What is the maximum time for the pitot heat switch to be “ON” while on the ground and does this switch heat anything else?
The PITOT HEAT switch shall not be on for more than 5 minutes on the ground. Power to the heater elements to the pitt tubes and the static ports
What are the ground operation limitations for the CH-47F?
To prevent droop stop pounding when all landing gear are in contact with the ground, and the Thrust Contr lever is at ground detent, flight control movements shall not exceed the following from the neutral position:
* Right or left directional pedal – 0.75 inch
* Aft cyclic – 2.00 inches
* Lateral cyclic – 1.00 inch
* Thrust Contr lever – No lower than ground detent
When are taxi directors and/or blade watchers required?
If necessary to taxi when less than 75 feet clearance exists between the centerline of the helicopter and obstruction, use taxi directors and blade watchers familiar with CH-47 turning characteristics.
How long is the aircraft from aft rotor tip to forward rotor tip with the rotor blades turning?
98 ft 10.7 inches
When do you have to check the FWD, COMB and AFT XMSN oil levels after shutdown?
COMB - within 30 mins of shutdown
FWD/AFT - after 30 mins
At what fuel quantity will the L FUEL LVL or R FUEL LVL be displayed on the WCA page (include associated NOTE)?
CAAS displays a caution, L FUEL LVL or R FUEL LVL, when the engines are running and the DCU reported left or right main fuel tank quantity is ≤ 360 pounds for more than 2 seconds.
This CAAS function serves as a back-up to the fuel quantity low level warning system.
This question has two parts:
a. The L FWD AUX PRESS advisory light activates during flight. What is the first thing you should do on seeing this advisory?
b. After this, you see that the L FWD AUX FUEL tank indicates 400lbs. You carry out the Checklist actions but the fuel remains unusable. What should you do with the fuel pump switch?
FUEL quantity — Check.
AUX FUEL PUMP switch(es) (inoperative
pump(s)) — OFF.
With an AUX Fuel Pump failed with 400 lbs. of fuel remaining, what considerations do you have regarding the total fuel indicated on the fuel page?
The auxiliary fuel tank status indicator is displayed as a white X over the fuel tank readout window to indicate usable (no X) and unusable (X displayed) fuel. When fuel is deemed unusable it is removed from performance calculations and from the total fuel symbology.
Where are the cross-feed fuel valve warning lights located on the A/C and what do they indicate?
Two press-to test engine fuel valve warning lights (Figure 2-29), one next to each engine fuel valve, indicate the operating condition of the respective fuel valve and associated circuitry.
Under what conditions will the XFEED fuel valve warning lights illuminate?
(a) Each time the XFEED switch is moved from CLOSE to OPEN, or OPEN to CLOSE, or when a FIRE PULL handle is pulled or pushed. Once the valve has completed its transit operation to either fully open or fully closed, the light should extinguish, indicating the valve is synchronized with the switch position.
(b) When a short circuit occurs, causing a
signal to be applied opposite to the valve position. However, the valve remains at the position last selected.
(c) When the valve protection relay fails. The valve remains at the last selected position and the valve can be operated manually, as required
Where can you find the list of fuels that may be used in a CH-47F?
Chapter 2
(1) Army Standard Fuels. JP-8 and F-24 are
the Army-designated primary fuels adopted for worldwide
use.
(2) Alternate Fuels. JP-4, JP-5, and equivalent
commercial fuels can be used continuously without
power reduction when Army standard fuel is not available.
Performance adjustments and increased maintenance
may be required when an alternate fuel is used.
(3) Emergency Fuels. 100LL (Low Lead) AVGAS
(Aviation Gasoline) is authorized for use as an
emergency fuel with operation not to exceed 6 hours cumulative
time and a DA Form 2408-13-1 entry required.
What is the difference between Commercial Grade A and A+ fuel?
Commercial fuel such as ASTM-D-1655 not containing an icing inhibitor per MIL-DTL-85470 (commercial name is “PRIST”). Use PRIST IAW the can instructions. Anti-icing and Biocidal Additive for Commercial Turbine Engine Fuel - The fuel system icing inhibitor shall conform to MIL-DTL-85470. The additive provides anti-icing protection and functions as a biocide to kill microbial growths in fuel systems. Icing inhibitor conforming to MIL-DTL-85470 shall be added to commercial fuel not containing an icing inhibitor during refueling operations, regardless of ambient temperatures. Refueling operations shall be accomplished IAW accepted commercial procedures.
What protective clothing and equipment will all crewmembers wear while performing crew duties?
The following clothing and equipment will be approved for aviation use and worn in accordance with AR 670–1, DA Pam 670–1, and CTA 50–900 by all personnel while performing crew duties:
(1) Identification tags.
(2) Under layer clothing made of cotton, wool, nomex, or materials approved.
(3) Flight suit.
(4) Boots.
(5) Flight gloves.
(6) Flight helmet.
What is the emergency procedure for ENG OIL CAUTIONS?
If engine power is not required for flight:
EMER ENG SHUTDOWN (affected engine).
Urgency to Land:
1. LAND AS SOON AS POSSIBLE — If
engine power is required for flight.
2. LAND AS SOON AS PRACTICABLE. — If
engine power is not required for flight.
When will the caution lights for ENG Engine Oil Low Quantity, High Temperature or Low/High pressure activate?
When either one or both of these cautions activate, about 2 quarts of usable oil remain in the respective engine oil tank.
If the ENG1 OIL HOT or ENG2 OIL HOT cautions are displayed, the oil temperature in the affected engine is at or above 149° C.
The ENG1 OIL PRESS LO or ENG2 OIL PRESS LO caution indicates oil pressure is below that which is required for the current NG speed in the affected engine.
The ENG1 OIL PRESS HI or ENG2 OIL PRESS HI caution indicates that the oil pressure in the affected engine is greater than 90 psi.
When has a rotor over-speed occurred?
A rotor over-speed exists when NR reaches 111.5%
When may a NP over-speed exist?
Power Turbine (NP) Limits. A power turbine (NP) overspeed may exist, depending on power being used when 106% NP is exceeded. The maximum limit for power turbine (NP) is 111.5%.
When has an NG over-speed occurred?
An NG overspeed exists when a speed of 111% NG is exceeded. An NG overspeed can cause over-temperature and/or over-torque.
Define ground resonance.
Ground resonance may develop in helicopters having fully-articulated rotor systems when a series of shocks cause the rotor blades in the system to become positioned in unbalanced displacement.
Identify the Cause of Ground Resonance
Groundresonance occurs when the helicopter contacts the ground during landing or takeoff (figure 1-83, page 1-66). If one wheel of the helicopter strikes the ground ahead of the others, a shock is transmitted through the fuselageto the rotor. Another shock is transmitted when the next wheel hits. The first shock causes the blades straddlingthe contact point to jolt out of angular balance.
Identify the Contributing Factors and Corrective Action for Ground Resonance.
Defective drag dampers allowing excessive lead and lag and creating angular unbalance. Improperly serviced or defective landing-gear struts. Hard landings on one skid or wheel. Ground taxiing over rough terrain. Hesitant or bouncing landings.
Corrective action may consist of an immediate takeoff to a hover or a change in rotor RPM to alleviate the condition and disrupt the pattern of oscillation.
Describe where the Proximity Switches are located and how they enhance ground handling.
Proximity switches (Figure 2-1), also referred to as the Weight-On-Wheels (WOW) switches, are installed on each aft landing gear. Each switch is activated when its associated shock strut is compressed during touchdown. When activated, signals from both switches are sent to the DAFCS to improve ground handling by reducing pitch axis gain of the DAFCS, cancelling stick input to the DASH actuators, and by driving both LCT actuators to the ground position. The associated L(R) GND CONT indicating lights on the Maintenance Panel will also illuminate.
Describe the functions of the Left and Right Weight-On-Wheels switches (include table and paragraph items).