SECTION IV
BLEED AIR SYSTEM
Systems:Air ConditioningAir Turbine Motor
Cabin PressurizationEngine air-inlet scoop anti-icing
Engine StartingLeading Edge Anti-icing
Nacelle Preheat (not 61st)Radome Anti-icing (not 61st)
Urinal Drain EjectorsWindshield Defogging
Valves:Inlet air duct and oil cool scoop a-i - press act, sol cont, energized clsd
Engine Starter - press act, sol cont, energized open, regulates press
Nacelle Preheat - press act, sol cont, energized open
Engine Bleed Air - motor driven
Lead Edge Anti-ice - press act, sol cont, energized open, regulates temp
Wing Isolation - manual open, spring clsd, sol con, energized open
ATM - press act, sol cont, energized open
GTC - press act, sol cont, energized open, regulates bleed load
AirCon & Undrflr Ht - press act, sol cont, enrgzd clsd, reg venturi flow
Radome Anti-Ice - press act, sol cont, energized open, regulates temp
When the flight station air conditioning is on the gauge reeds 6 PSI lower than actual.
AIR CONDITIONING
Principle components: venturi regulator, electrical temp cntrl, water separator, refrigeration unit, aux vent valves and cntrls, and distribution ducts.
Airflow Regulators: Flight Deck - 30 ppm (15 ppm in AIR COND GTC position)
Cargo Comp - 70 ppm (27 ppm in AIR COND GTC position)
Temperature Control: Automatic - 5 mins from each extreme to the other
Manual - 4 mins full cold to full hot, 35 secs full hot to full cold
Refrigeration: 1st stage - heat txfr between bleed air and ram air
2nd stage - turbine which drives the cooling air fan
Water Separation: removes 80% with cone shaped bag and drain
When the temp selectors are moves all the way to cool fog may enter
Underfloor Heat: Heats floor to approx 80 and turns on overhead duct aux fan
Aux Vent: admits ambient air under ram pressure or external air conditioning. Prevented from opening until diff press is 0.28 psi (0.6 inHG)
Flight Deck Refrigeration Shutoff Valve Override: Pull - closes flow regulator
Push - opens regulator if pressurized
Neutral - normal ops
Emergency Depressurization: Closes both a/c flow regulators and opens outflow and safety valves.
If the engine bleed air valves are open and AIR COND GTC the cargo compartment flow regulator will open fully. There may not be sufficient air to operate ATM and flight deck a/c.
CABIN PRESSURIZATION SYSTEM
Outflow Valve: Right side at the aft end of the flight deck (Navs feet)
Safety Valve: Left side of the cargo door. Set @ 15.9 and -0.76 inHG
Cabin Pressure Controller: Set to -1,000 to 10,000 feet If forced you can damage
Manual Pressure Control Switch: Deliberately driving the outflow valve to close resulting in the safety valve opening is prohibited. When switching from auto to manual you must depress the switch for 40 secs to gain cntrl.
Do not pressurize the aircraft during ground ops to allow for rapid egress.
The diff press will be 0 for landing. If less than 0.5 inHG there will be no discomfort if you go depressurize.
Do not lock or unlock any window, door, or hatch while pressurized. First depress then goto AUX VENT.
ANTI-ICING AND DEICING SYSTEM
Pneumatic: Wing & Empennage leading edges, radome, and engine inlet air duct and oil cooler scoops. Compressor inlet guide vanes are heated directly from the compressor.
Electric: Windshields, pitot tubes, and the fwd part of propeller spinner and afterbody. Deicing is accomplished for the prop blades and rear part of spinner.
Automatic Ice Detect: Radome, inlet air duct and oil cooler scoop, compressor inlet guide vane, and all props. #2 & #3 engine detectors work when in RUN and in AUTO. Automatically turns on, goto RESET to turn off.
Leading Edge: 350F air with sensors to keep between 158-180. Overtemp 200.
Do not use to remove ice on ground. Test on the ground limit 30 secs.
Wing: Indicators and LightsEmpennage: Indicators only
Engine Inlet Air Duct: If an engine is shutdown in flight this should be left on if icing conditions exist. This is not possible with the fire handle pulled.
Propeller: Fwd section of front spinner and afterbody (A) are anti-icing and continuous. Aft section of front spinner (B), fwd section of rear spinner (B), aft section of rear spinner (C), spinner plateaus (B), and leading edge of blades (C) are deicing and 15 secs per blade.
Do not fly into icing if below 65 amp for 15 secs in 1 min cycle.
Use on the ground only if engine running and no more than 2 cycle.
Can be used on feathered prop.
NESA Windshield: 3 front, 2 on each side of front, 2 lower on pilots side. High only means more voltage to heat quicker but heats to same temp as normal. Use coldstart if below 43C (45) for 5 secs on and 10 secs off. If above 27C (81F) then you can delaminate the panels if NESA is used. If turned of the strength of the window is reduced. If a panel with thermistors is not heating, excessive heat, or electrical arcing then turn it off.
COMMUNICATION AND ASSOCIATED ELECTRONIC EQUIPMENT
Do not use other nonsecure communications (including interphone) when using secure-voice.
INTERCOMMUNICATION SYSTEM - All but cargo-compartment can hear outside communications. The P, CP, N & Instructor panels are the only who can transmit. On some airplanes HOT MIC will not work on INT or UHF-2. Using one of the switches will override HOT MIC line.
PUBLIC ADDRESS SYSTEM - 7 speakers: ALL (all but ramp), FWD (one speaker in front), AFT (ramp only), JUMP (2 speakers next to paratroop doors)
VHF - AM and FM capability for 4,080 total channels. FM - 30.000 to 87.975
AM - 116.000 to 151.975 (TX/RX) 108.000 to 115.975 (RX Only)
1 minute warmup
SECURE VOICE - KY-58: VHF & UHF KY-75: HF
UHF - 7,000 225.000 - 399.975. 1 minute warmup. # 1 cntrl head overrides SCNS
Do not use the auto selection on the antenna selector.
When using guard in an emergency, go to GUARD and MAIN. If you use BOTH then the signal may be unintelligible.
HAVE QUICK - Tone will be heard in “AJ” if an invalid active net is selected, TOD has not been received, or WOD has not been entered. Radio will automatically receive the first TOD it receives after power up. Selecting GUARD disables “AJ” mode.
MARKER BEACON - OM:blue/400 cps IM:amber/1,300 cps Airway:white/3,000 cps
To select a narrow band width then select LO when at high altitude.
VOR/ILS/MB - 200 channels (160 VOR and 40 localizer) 108.00 - 117.95
Do not test with autopilot engaged.
TACAN - 126 channels each for x and y. 90 secs warmup.
Do not test with autopilot engaged. When Tacan is primary navigation source the nav will not select tacan on either BDHI/RMI. When P & N have TAC 1 and CP has TAC 2 then BDHI can have 10 error.
In air-to-air the receiver selects a channel 63 from other aircraft. Use of y is recommended in a-a mode. To prevent interference from IFF then select y or use x channels 11-58, 74-121.
FLIGHT DIRECTOR - Consist of computer, ADI, HSI, rate gyro, MD-1 gyro, rate of turn sensor, and selector switch. Should use the Ess AC selection on the CP INST Bus during flight. If you are using standby and you get jittery indications then select HDG and NORMAL. If you get a failure of ADI in Ess AC position then got to standby power.
ADI repeat only works if P has VOR/ILS 1 or 2 selected and a valid ILS frequency tuned.
Do not put both Vert Ref switches in INS @ same time.
RADAR ALTIMETER - Unreliable over large depths of snow. Does not look forward for terrain clearance on low-levels, just directly below aircraft. 16-32 secs calibrations time.
ADF - 100 to 1,750 kilocycles. 5 minute warmup.
RADAR - 3 minute warmup. Dangerous voltages (15,000 volts) are in the radar set, so don’t make internal repairs or adjustments. Before selecting Search, Beacon, or Warning make sure people are clear. Don’t use or direct beam around aircraft being refueled. Have stabilization off while taxiing, prior to landing, or inflight in STBY. Otherwise have it on.
Leakage Test: Momentary ON until 40 inHG. It should hold within 2 inHG for 10 minutes. Don not allow it to go above 41 inHG. Do not operate radar until 27-32 inHG.
AIMS - Air traffic control radar beacon, Identification friend or foe, Military equipment, Special systems. Must be in NORM for self test. The audio option for Mode IV is inoperative. Both Audio and Light will give you the light. HOLD will retain codes with power loss if gear is down and locked. IDENT: 15-30 secs plus how long you hold it. TEST: if you hold it the light will remain on and it may blink once after you release it.
AUTOPILOT - Warm up 3 mins when ESS AC & DC are powered. It will only turn ON when warmed up, servos disengaged, turn knob in center, and in gyro pilot. Do not use below 1,000’ agl unless on a couple ILS, then monitor controls continuously. Max speed: 250 knots. Max weight: 155,000 lbs. Make sure its trimmed for hands off flight before engaging. Check the autopilot trim indicators have an average of 0 before engaging, and always monitor them. Do not overpower controls. Do not engage in a turn or just after a prolonged turn. Prior to disengaging hold wheel and pedals. Passing thru 200 knots retrim the rudder axis. Go to altitude hold with less than 300 fpm. Return turn knob to center slowly or the AP can overshoot rollout. With altitude hold on retrim the plane with 20-30 knots change. If not on course it will turn to a 60 intercept heading. While in the cone of confusion you can change course 30 and between stations 5.
N-1 COMPASS - Analog style compass. If either compass fails then you can get inaccurate info. Erratic movement of the heading pointer is a malfunction, that master cannot be relied on. Disengage AP rudder.
# 1: P - HSI compass card, FD bnk strng bars in DOP, TAC1 or VOR ILS 1
CP - RMI/BDHI compass card, FD BSB in “ “ “
N - Right RMI/BDHI compass card
Also autopilot, search radar, and TAC 1 and VOR/ILS 1
#2: P - RMI/BDHI compass card, FD BSB in TAC2 or VOR/ILS 2
CP - HSI compass card, FD BSB in “ “
N - Left RMI/BDHI compass card
Also TAC 2 and VOR/ILS 2
5 minute warmup when Ess AC & DC is powered. Allow for synchronization before use. Reset the latitude every 2. #1 and #2 should be within 2 of each other. Each remote would be within 2 of respective master. Masters should be within 1 of actual aircraft heading. Precession should not exceed 3 per hour.
C-12 COMPASS - Digital type set up the same as N-1 except: #1 and #2 within 2 of each other 3 minutes after a turn, inside of 3 minutes its 4 and the precession rate is 2 per hour.
EXTERIOR LIGHTS
Landing Lights: 2 under wing, Ess DC (do not operate for prolonged time on gnd since there is no cooling)
Taxi: 2 on gear doors, Main DC
Wing Tip Taxi: 2 on wing tips, Main DC
Formation: 9 (3 on each wing, 3 on top aft of wing), Main DC
Navigation: 6 (red on left wingtip, green on rt wt, 2 white on tailcone, white on top of fuselage, white on bottom of fuselage), Ess DC
Anti-collision: 2 (white/red on top of vert stab or top of fuslge and bot of fuselage), Ess DC, Use in IMC is not recommended, can damage eyes within 10 feet
Leading Edge: 2 on both side of fuselage, Main DC
Signal Lamp: Main DC, Red Amber Blue and Green
INTERIOR LIGHTS
P/CP Inst and Engine Inst: Ess AC, Fuse protected @ Fwd FS 245, 6 volt light bulbs
CP Secondary: Flood lights, Isol DC, 28 Volt bulbs
P & Eng Secondary: Ess DC, 28 Volt bulbs
SCNS: Main AC
All others are Main DC and 28 volt bulbs
OXYGEN
300 psi good for 96 manhours minimum
6 regulators (6 on flight deck, 4 in cargo compartment)
Portable chargers @ P, CP, rt side aft 245, and aft rt wheel well.
When on 100% less oxygen is consumed at higher altitudes, so to increase duration then increase cabin altitude.
As flow increase then temp decreases, which results in lower pressure. You can limit use to warm it up again. If drop in temp or press or a lack of flow then reduce crews need by change in flight environment or regulator settings. As a last resort put crewmembers on portable bottles, EEBD, or POKs to reduce usage. Recharging bottles can increase system degradation. Make sure masks fits face or you can deplete the supply. Unless you need unscheduled pressure increase leave the switch in NORMAL.
2 heat exchangers warm the oxygen. Test: On/100%/EMER, breath normal for 3 cycles and watch blinker, hold breath (blinker black), NORMAL (blinker stays black), breath normal for 3 cycles and watch blinker, leave in NORM/100%/ON and connected.
GTC
Provides pneumatic air for ground ops of ATM, engine starting, nacelle preheat, and air conditioning.
Compressor: 2 stage centrifugal type
Power Turbine: combuster and turbine(some air turns turbine and rest goes to aircraft)
Accessory Assembly: “GOOFS”
Governor: regulates FF to keep @ 100%, shutdown if overspeed
Oil Pump: 1 main 2 scavenge 1 filter
Oil Cooler & Fan: If 25C(81F)
Fuel Pump: can be fed from any tank thru xfeed manifold. Strainer removes water and acts as filter
Starter: Door must be fully open. When oil pressure reaches 3psi (@12%) then fuel and ignition circuits are energized. Disengaged by centrifugal force @35%.
On Speed Light: 95% switch keeps you from opening bleed valve
Door Warning Light: On when door is not closed
Start Light: On whenever starter is on.
If start light does not go out after 1 min then stop.
If GTC does not lightoff then maybe lack of oil in line. You can prime this oil line.
If DC power is interrupted then GTC will stop.
Ensure 1 min warmup before applying load.
Start: DC pwr, Opn Dr, Tie Bus, Open Xfeed, close bleed air, Start
Load: On speed, wait 1 min, bleed air open, check pressure
Stop: Close bleed air, cool down 1 min, GTC off, close door
ATM
In left wheel well above and aft of GTC
Single stage axial flow turbine
Speed controlled by speed sensing butterfly valve
CARGO COMPARTMENT EQUIPMENT
Tiedown fitting: Floor-10,000 Ramp/Sidewall-5,000 Threaded sockets-25,000 (12 fittings stowed in cargo door)
Cargo nets stored left and right sidewall above ramp.
Snatch blocks stored aft of 245. Connect to threaded sockets below 245.
Wheel prybars can be used singly or pairs. Good to 5,000 lbs but floor isn’t.
Aux ramps - 4 (2 truck & 2 ground loading) rt sidewall above ramp
Portable winch - use 10,000 tiedown.
CARGO RAMP AND DOOR
Electrically and manually controlled from aft control panel. Electrical only from the ADS control panel in the cockpit (inop on the ground)
Exercise caution when using manual handle, some aircraft use down to close and others use up to close.
Leave controls in neutral or else they may move when aux hyd pmp is on
The uplock emergency release handle is aft of left paratroop door.
Gauges - CP is electric and the aft one is direct reading
Ramp/Door Open light - door fully open and ramp in ADS position
Cargo Door uplock indicator - flag in view when uplocked
The ramp can be stopped anywhere but the door will freefall if not uplocked
To close door - goto open then pull uplock release. Allow to freefall. If not locked then goto close.
AIRDROP SYSTEM
If you release the switch the ramp stays and the door freefalls unless locked
When the switch is in open the Door Warning light comes on regardless of the position of any door.
For chute release to operate the ramp/door must be in the ADS position
Ensure all people are clear between cargo and open ramp/door before placing the AD/TJ switch in any position other than manual.
64 paratroopers (24 inch spacing), 78 ground troops (20 inch spacing) you get an additional 14 is you use the wheel well wall seats for a total of 92.
70 litters with 6 attendants and 73 litters with 4 attendants
Paratroop doors - stand clear when opening or closing. The pip pin will be in locked position with door closed only on the ground to secure plane.
Electric control of ramp/door is inactivated when anchor line support arms are not up. If door is opening it will freefall and ramp will stop.
Static line retriever will not be used to load cargo. If you have one with a slip clutch, then reverse direction to reset, determine overload and continue.
The static line retriever runs for 3 secs when CDS armed and green light on
Only are CDS switch when operational check and mission requirements dictate.
Make sure you have 10 ft unwound before operational check.
Jump lights - 9(fwd/aft each paratroop door, each anchor cable support arm, fwd cargo compartment @ interphone panel, and next to P & CP)
Air Deflectors - 15.5 inches, provides windbreak for paratroopers. The light comes on if doors are not completely closed. They will close if any switch is on close regardless of position of other switch.