Aviation Maintenance Alerts
Total Page:16
File Type:pdf, Size:1020Kb
ADVISORY CIRCULAR 43-16A AVIATION MAINTENANCE ALERTS ALERT DECEMBER NUMBER 2008 365 CONTENTS AIRPLANES BEECHJET..................................................................................................................................1 CESSNA ......................................................................................................................................1 LUSCOMBE................................................................................................................................3 PIPER...........................................................................................................................................5 HELICOPTERS SIKORSKY..................................................................................................................................6 AIR NOTES INTERNET SERVICE DIFFICULTY REPORTING (iSDR) WEB SITE.................................6 IF YOU WANT TO CONTACT US...........................................................................................7 AVIATION SERVICE DIFFICULTY REPORTS .....................................................................7 December 2008 AC 43-16A U.S. DEPARTMENT OF TRANSPORTATION FEDERAL AVIATION ADMINISTRATION WASHINGTON, DC 20590 AVIATION MAINTENANCE ALERTS The Aviation Maintenance Alerts provides a common communication channel through which the aviation community can economically interchange service experience, cooperating in the improvement of aeronautical product durability, reliability, and safety. This publication is prepared from information submitted by those who operate and maintain civil aeronautical products. The contents include items that have been reported as significant, but have not been evaluated fully by the time the material went to press. As additional facts such as cause and corrective action are identified, the data will be published in subsequent issues of the Alerts. This procedure gives Alerts’ readers prompt notice of conditions reported via a Malfunction or Defect Report (M or D) or a Service Difficulty Report (SDR). Your comments and suggestions for improvement are always welcome. Send to: FAA; ATTN: Aviation Data Systems Branch (AFS-620); P.O. Box 25082; Oklahoma City, OK 73125-5029. (Editor’s notes are provided for editorial clarification and enhancement within an article. They will always be recognized as italicized words bordered by parentheses.) AIRPLANES BEECHJET Beechjet: 400A; Cracked Bleed Line Brackets; ATA 5312 A technician for an operator describes a repeating defect for this model aircraft. "While performing an A-B Inspection (I) found the right aft fuselage bleed air line attach brackets pulled (free) from the aft fuselage bulkhead—resulting in cracks in this part (bulkhead P/N 45A34901-11) at frame station 329.92. I recommend (scrutinizing) this area thoroughly at each inspection—contacting Hawker Beechcraft (if necessary) for repair options. "This is the fifth aircraft in a row that this (particular) bulkhead (has been found) cracked, occurring on both left and/or right hand sides (of the fuselage)." (A search of the FAA Service Difficulty Reporting System database revealed only two entries for this bulkhead part number—maybe the other three occurrences didn't get submitted? Also--please note the missed opportunity for a couple of dramatic photos! It's easy to miss the mechanical "importance" through endless words—a couple of closeup photos will command much more attention—Ed.) Part (aircraft) Total Time: 3,053.6 hours. CESSNA Cessna: 172A; Broken Control Wheel; ATA 2701 A technician states, "Upon taxiing from the refueling (location) the pilot was making a left turn in front of the hanger. He pulled the control wheel full aft (to take the weight off the front wheel)—then the control wheel broke off in his hand. (Ambient) air temperature was approximately 20 degrees. This break (formed across the wheel...) from the lower left to the upper right (7—2 o'clock)." Page 1 December 2008 AC 43-16A (Control wheel P/N: 0513168-2. A search of the FAA Service Difficulty Reporting System database revealed only three occurrences of this part number; however, truncating up to the last three digits yields 61 of these kind of failures!) Part Total Time: (unknown). Cessna: 172S/T206: Loose Fuel-Servo Plugs; ATA 7322 (The following description combines four defect reports on the above two aircraft models: three 172's and one T206. All four reports were written by the same repair station technician and describe the same defect—with the indicated differences.) 172's: "While performing Precision Service Bulletin PRS-107 (I) found the (fuel servo's) hex-nut plug finger loose (P/N 383493). (A note indicates a warm engine will probably make this condition more apparent.) I suspect this (plug) was (improperly torqued) from the factory." (Fuel servos - Precision: RSA-5. Part times: 31.8, 449.5, and 504.0 hours.) T206: "While performing Precision Service Bulletin PRS-107 (I) found the (fuel servo's) hex-nut plug finger loose (P/N 383493). Red dye was also found inside the fuel servo air chamber. This aircraft has had an issue with lean idle mixture in the past. (A note indicates a warm engine will probably make this condition more apparent.) I suspect this (plug) was (improperly torqued) from the factory and the red dye was not flushed from the chamber. (This unit) was sent to the overhaul facility to have (these defects) corrected—and the requirements of PRS-107 Service Bulletin (complied with)." (Fuel servos: Precision: RSA-10. Part time: 309.2 hours.) (A search of the FAA Service Difficulty Reporting System database revealed six entries for this loose plug.) Part Total Times: 31.8, 449.5, 505.0, and 309.2 hours (respectively). Cessna: 207; Failed Fuel Pressure Hose; ATA 7310 "The metered-fuel, pressure hose failed," says the submitting mechanic. "This hose runs from the fuel injector distributor to the firewall. A low pressure test of the failed hose revealed multiple leaks along (its) length. This hose was installed in April 2003—(the leaks discovered) in February 2008 (from intermittent engine operation). The hose time in service was 1563.0 hours. The following information was noted on the identification tag: Stratoflex PT/BA, 156mA001-3SO350, CDQ02WO8316, OP1500PSI, TSOC53a.A, C75I/II-A-S/P, A12/12/02, OT275F. This hose was part of an Aviall hose kit, number 2738916 dated 12/12/02. In the recent past this same hose (on another aircraft in our fleet) has had the same type of failure at (approximately) 1600 hours in service." (A Cessna part number was not included with this submission—Ed.) Part Total Time: 1,563.0 hours. Cessna: 210; Failed Oil-cooler Gasket; ATA 7921 An A&P mechanic holding an inspection authorization states, "The oil cooler adapter gasket failed in flight, causing two quarts of oil (within one hour) to be pumped into the engine cowling. This engine (IO520) is a Continental factory remanufactured engine with 140 hours since November 2004. On inspection and disassembly the oil cooler adapter bolts did not appear to be torqued (properly)—but the gasket itself was brittle and leaking (P/N 649964). The engine and adapter surfaces were (both) flat and clean. This is the second time I have Page 2 December 2008 AC 43-16A witnessed this failure on these remanufactured engines. The replacement gasket appears to be a better quality—I think Continental should (investigate) this problem. This engine holds 12 quarts of oil: when it's gone you are landing...." Part Total Time: 140.0 hours. LUSCOMBE Luscombe: 8E; Broken Carburetor Heat Muff; ATA 7160 (This particular airplane has a Continental C-85-12F engine under the hood.) Another A&P/IA mechanic says, "After a flight it was noted a portion of scat hose was hanging from the bottom of a cowling opening. Inspection found the carburetor heat flange had separated with the scat hose and attached clamp from the inboard half of the right carburetor heat muff. The heat muff halves were removed and inspected. Examination of the failed round duct flange found the entire tube broken off at the circumference along the edge of the weld. Secondly, there were about six "spider-like" cracks around the broken hole, propagating outwards. A total of 16 cracks and broken tabs—including a previous "patch" repair were noted on both inboard and outboard muff halves. An inner muff rib which was tack-welded in three places had one tack weld broken, and on the opposite (outside) were slight burn-through areas (also having) two small cracks (from these tack-welds). "This part was stamped by Univair Aircraft Corporation (P/N U086126). It had approximately 560.5 hours time in service. According to Univair the type alloy material used in the FAA/PMA part is 2024-T3. AC (Advisory Circular) 43.13-1B (paragraph 4-89d) mentions '...2024 and 7075 Aluminum. Do not weld these two aluminum alloys....' This (part's) material is contrary to the FAA Advisory Circular and to ASTM and AWS codes and standards in welding." Page 3 December 2008 AC 43-16A Page 4 December 2008 AC 43-16A (This report is particularly strange—given no one on planet Earth with the least welding experience could long endure coaxing 2024 not to crack—Ed.) Part Total Time: 560.5 hours. PIPER Piper: PA18-150; Broken Main Gear Cabane Fitting; ATA 3213 "The pilot stated he performed an off-airport landing along a beach while hunting in Western Alaska," says this submitter. "Upon landing, the upper R/H main landing gear cabane fitting broke. The landing gear safety cables prevented a total gear collapse." (The