THE B-17 FLYING FORTRESS ENGINE STARTUP

[Music] [Music] so [Music] there contact [Music] wherever men fly the flying fortress there must be skilled mechanics to care for the ship to assure its maximum performance these mechanics must be trained in the flying portrait school or be fitted by practical field work to meet all necessary qualifications starting engines or the pre-flight engine run is just the first simple but important instruction in a mechanic's basic training a crew of these men under the supervision of a crew chief is required the procedure of starting engines illustrated in this picture is based on the boeing preliminary handbook of instructions and directed by competent technical advisors this procedure is subject to revisions to meet actual field requirements such revisions are as necessary as the change of clothes men must wear in tropical heat or in arctic cold these two crew mechanics are going through the ship to the cockpit they will be called a pilot and co-pilot the pilot mechanic is usually the crew chief the pilot after seating himself makes seat adjustments he does this for two purposes first to place himself comfortably secondly to be within easy reach of all controls the rudder pedals are reset to fit the man the pilot properly seated removes the steering control lock and places the pin in its holder the flight controls and the tail wheel are in turn unlocked chalks are placed in front of the wheels this is a precaution in case the hydraulic pressure on brakes is not sufficient to prevent the airplane from rolling while the men in the cockpit are adjusting controls previous to starting and warming the engines mechanics on the ground are giving the ship a visual inspection the engine and nacelle callings are inspected to see that they are properly secured wing surfaces are visually inspected for any damage such as temp cracks breaks or missing rivets detailed surfaces are also inspected a number of skilled mechanics can make a complete rigid visual inspection of the ship's surfaces in a surprisingly short period of time when the quantity of fuel and oil has been entered in form one it is returned to the crew chief in the cockpit back in the cockpit the pilot mechanic turns on the battery switches and pushes the master switch to on position pressure must be built up in hydraulic system for application to break and call flat the globe valve is opened between the service and emergency accumulator the selector valve is then turned to servicing position when the hydraulic pump cuts in pressure is built up in both accumulators when sufficient pressure has been reached the hydraulic pump cuts out automatically [Music] the globe valve is placed in former closed positions before the co-pilot returns to the cockpit again seated the co-pilot sets the parking brake this is accomplished by depressing the pedals and pulling out the brake rod knob the throttles are placed in closed position mixture control handles are set at idle cut off to prevent the engine from building up turbo pressure when starting supercharger controls are placed at off position the pilot next places the propeller pitch control in low pitch position so that the propeller will have a low blade angle when the engine is started the cowl flap selector valves are turned to open position and the cowl flaps open in case of over priming this gives the ground crew access to any fire which may occur around the engine exhaust collector ring while engines are being started the call flap selector valve must always be returned to lock position after the flaps have been opened the engines are now ready to start and the pilot makes certain that the magneto switches are in the off position a switch left on to neglect may cause serious injury to men involved in ground operations the all-clear signal is given the propellers are then pulled through to free the combustion chambers of any oil which may have accumulated during the period the airplane was idle failure to do this will cause serious damage to the engine the artisan inverter is switched to normal position alternating current is necessary in operating autosyn instrument the throttle is set one quarter open the correct starting position boost pump supply fuel to the carburetor and the pump switches are turned on the mechanic in the co-pilot seat sets the fire extinguisher selector to the engine being started then setting the primer selector the co-pilot primes the engine an extra safety measure is taken in starting each engine a mechanic stands by with a fire bottle throughout the starting operation the pilot signals the ground crew number one magneto switch is turned on the starter switch is set to start where it is held from 12 to 15 seconds it is then pushed to mesh when held in meshed position high voltage from the booster coil is supplied to the magneto until engine starts in the event of slow starting the co-pilot again primes [Applause] the pilots move their mixture control to automatic bridge the oil pressure should rise within a few seconds after the engine starts to be sure that the fuel pump is operating properly the fuel pressure gauge is observed the manifold pressure is also noted um [Applause] [Applause] [Applause] [Music] [Music] the pilot checks the vacuum gauge the vacuum selector handle is turned from left to right to check the operation of both vacuum pumps attention is given to the cylinder head temperatures during the warm-up the temperature may be controlled by the engine cowl plant this temperature should not exceed the allowable limit which is 205 degrees centigrade with the engines running at 1800 a check is made of the generator the voltmeter selector knob is switched to generator tested and the voltmeter is observed a check is also made of generator output during the engine warm-up the oil temperature is observed it is necessary that the oil reaches the proper operating temperature the de-icer selector is turned on an alternating pressure and vacuum causes the dehyzer boots to pulsate this alternate pressure and vacuum is distributed by an electrically driven distributor valve to the respective cells in the de-icer boot after all de-icer boots have been thoroughly inspected the selector valve is returned to off position number one throttle is open to 1800 the propeller pitch control lever is placed at high pitch when blades reach high pitched position engine speed drops to approximately 1100 rpm a considerable rise in manifold pressure is noted the controls are then returned to low pitch tachometer returns to 1800 and the manifold pressure drop when engines are running at 1800 right and left magnetos are checked to determine if magnetos and spark plugs are functioning properly the pilot now moves the supercharger control handle forward he opens the throttle the manifold pressure should read 46 inches and the tachometer reading 2500 rpm pilot is now satisfied that the engine is developing full power he pulls the supercharger handle back to off he then closes throttle down to 1000 rpm cylinder head temperatures are constantly observed and should never exceed 205 degrees centigrade during ground operations the run-up is repeated on all four engines the cowl flaps are left open until the cylinder head temperatures reach 150 degrees or 160 degrees centigrade then the pilot is ready to stop the engine to stop the engine the mixture control handles are moved to idle cut off the throttles are open slowly to clear gas from carburetor accelerating pumps the pilot turns the magnetoswitch to off all other electrical switches are then turned off the job is finished the engines have been started and functioned perfectly a visual inspection of the ship has been made the procedure has been followed step by step adjustment of controls preliminary to starting the engine the actual starting of all engines by these skilled mechanics every step has been checked on the form which the crew chief now delivers to the product everything okay there no other phrase can be more pleasing to the pilot everything okay the flying fortress is ready for the job ahead [Music] so you