Beechcraft Duke 60 Series Maintenance Manual

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34 Navigation & Pitot/Static CHAPTER SECTION SUBJECT 34 -EFFECT I VITY /CONTENTS 34 -00-00 34-10-00 SUBJECT GENERA L Description and Operation Instrument Access Instrument Operation FLIGHT ENVIRONMENT DATA Description and Operation Troubleshooting Pitot and Static Pressure System Maintenance Practices Pitot System Leak Test Pitot System Hose In spection Static System Cleani ng Static System Leak Test BEECHCRAFT DUKE 60 SERIES MAINTENANCE MANUAL CHAPTER 34 LIST OF PAGE EFFECTIVITY CHAPTER 34- NAVIGATION TABLE OF CONTENTS " END" PAGE 1 101 201 202 CHAPTER SECTION SUBJECT 34-00-00 34-10-00 DATE Nov 2/ 73 Nov 2/73 Nov 2/73 Nov 2/73 Nov 2/ 73 Nov 2/ 73 PAGE 1 101 101 20 1 201 201 20 1 201 34-EF FECTIVIT Y /CO NTENTS Page 1 Nov 2/73 BEECH CRAFT DUKE 60 SER IES MA INTENANCE MAN UAL GENERAL - DESCRIPTION AND OPER ATION INSTRUMENT ACCESS Engine instruments may be removed with the instrument panel in place. Pull the post-light shield straight off to provide clearance for the instruments. Loos en the retaining screw located below and to the left of the instrument, loosening the instrument retaining clamp. Suffici ent wiring has been installed to enable you to pull the instrument out. To gain access to th e other instruments remove the four screws attaching the LH or RH panel door and pu ll it out far enough to disconnect plumbing and wiring, freeing the panel for removal. NOTE To avoid marring the finish, wrap padding around the control columns just be low th e instrument panel. The glare-shield may be loosened and tilted back by releasing the four clips located on the underneath side. INSTRUMENT OPERATION The gyro instruments operate on filtered air provided by the pneumatic pressure system. Adjustment of the pneumatic pres.sure system is performed by adjusting the various regulators in a specified sequence. A PRESSURIZATION SYSTEM ADJUSTMENT CHART cor responding to app li ca ble illust ratio ns and a gene ral ad j ustme nt pro cedu re for eac h individual regulator is pro vided in Chapter 36 · 00 -00. The air speed indicator, altimeter, a nd rate -of -climb indicator operate on air provided by the pi tot and static pressure system. (Refer to Chapter 34·1 0-00 .) An Overhaul and Replacement Schedule for instruments u tilized by the Duke series aircraft is found in Chapter 5-00·00. " END" 34 -00 · 00 Page 1 Nov 2/73 BEECHCRAFT DUKE 60 SERIE S MAINTENANCE MANUAL FLIGHT ENVIRONMENT DATA DES CRIPTION AND OPERATION The pitot and static pressure system provides a source of ram and static air for instrument operation. Ram air enters the pitot tube, located on the LH lower side (P-4 th rough P- 1 52) or the RH lower side (P-1 53 and after) of the nose section forwa rd of the nose landing gear doors, and is routed to the pilot's airspeed indicator. A heating element is installed in the pitot mast to prevent the mast from becoming obstructed by ice. Static air is taken from a static air port, located on each side of the aft fuselage. The static air is routed along the right side of the fuselage to the cabin differential pressure gage, rate-of-climb indicator, altimeter and airspeed indicator. Shou ld the normal static system become inoperative, an emergency static air source control, located on the upholstery panel forward of the copilot's seat, may be opened to provide a source of static air. The emergency air port is located on the aft pressure bulkhead. The drain valves are located on the RH lower upholstery panel. NOTE When dual instruments are installed an optional dual pitot and static system is utilized. The optional pitot mast is plumbed to the copilot's ai~peed indicator. The optional static air ports are located, one on each side of the aft fuselage and are plumbed to the copilot's rate-of -climb indicator, altimeter and airspeed indicator. " END" 34-10·00 Page 1 Nov 2n3 TROUBLE 1. Heating element inoperative. 2. Circuit breaker keeps tripping. 3. Instruments inoperative or erratic in operation. BEECHCRAFT DUKE 60 SERIES MA I NTENANCE MANUAL TROUBL ES H OO TI NG PI TOT AND STA TI C PRESSURE SYSTEM PROBABLE CAUSE a. Defective switch. b. Grounded or open circuit. c . Defective heating element in pitot head. a. Grounded wire. a. Lines clogged. b. line leaks. "E ND " a. b. a. b. REMARKS Replac e. Check for continuity. Drain lines at emergen cy stat ic drain . Di sco nnect lines at instruments and blow ou t with low pressure air. Check lines for looseness at all connection points . 34-10-00 Page 101 Nov 2/73 BEE CHCRAFT DUKE 60 SERI ES MA INTENANCE M ANUA L FLI G HT EN V IRO NM ENT D A T A MA INTE NA NCE PRAC TI CES (Figure 201) PITOT SYSTEM LEAK TEST A functional test of the pitot system can be made by using an observer in the cabin to watch the airspeed indicator while air pressure is built up by using a section of soft rubber tubing as follows : a. Clamp the rubber tubing over the pitot mast inlet, making certain that the connection is air tight. b. Crimp the end of the tubing and slowly roll it up until the airspeed indicator registers approximately 90% of its maximum reading. CAUTION To avoid rupturing the diaphragm of the airspeed indicator, ro ll up the rubber tubing slowly and do not build up excessive pressure in the line. c. Secure the rolled up t ubing so that it will hold the airspeed indicator reading. d. If there is no decline in the reading after several minutes, th e re is no leak in the pitot system. e. If a decline in the reading of the airspeed indicator is observed, check the pitot system plumbing for leaky hoses and loose connections. CAUTION Release the air pressure slowly by unrolling the rubber tubing; a sudden release of the air pressure may damage the airspeed indicator. PITOT SYSTEM HOSE INSPECTION After the pitot system is chec k ed for leaks, inspect the hose sections for signs of deterioration. Check all polyethylene tubing for hardness or britt leness. Rubber hoses on which