COMANCHE TECH TALK
While comanchepilot.com is basically dedicated to the Comanche, articles on any aviation subject from other owners and pilots are welcome. Our first guest author is Tom Turner of the American Bonanza Society, whose work on safety issues has been quoted in previous Comanche articles.
by Thomas P. Turner, ABS
"We pulled your airplane out of the hangar," the mechanic says on the phone. "Everything's ready for you to come pick it up."
Your airplane's been in the shop for repairs. The annual inspection's complete. Maybe you've had it painted, or installed an upgrade. Whether the airplane was "down" for something as simple as an oil change or as intrusive as an engine change, it's wise to thoroughly check it before flying away from the shop.
Most mechanics and installers are professionals—there's no disputing that. Like pilots, though, they are also people—and subject to the same human factors that sometimes hinder even a good pilot's performance. People, even the finest mechanics, sometimes make mistakes. Fatigue, stress and distraction are part of the mechanic's world, too. As pilot you also play a vital part in the team effort of returning the airplane to service. Remember, it's your life, and those of your passengers, on the line.
I've picked up airplanes from the shop dozens, if not hundreds, of times fromextremely reputable mechanics, and still found airworthiness squawks. I've even accepted delivery of brand new airplanes that weren't airworthy. Over the years, I've developed a process, a post-maintenance inspection, that I follow whenever the mechanic tells me he or she is finished with the airplane.
Begin with the documentation that makes the airplane legal for flight (requirements will vary for airplanes registered outside the United States).
1) Basic Documentation. Check the following:
a) Airworthiness Certificate: Ensure the correct certificate is in the airplane.
b) Registration: Check that the proper registration certificate is also in the airplane—and your address is correct. Remember that this is the address used to provide you Airworthiness Directives and other critical safety information, so it's vital (and the law) that this address is current.
c) Radio Station License: If your airplane has a Federal Communications Commission (FCC) Radio Station license, make sure it's still in the airplane. This document is required only for U.S.-registered airplanes that will be flown outside the United States.
d) Operating limitations: Operating limitations information must be in the airplane. Many limitations are contained in placards or marked on aircraft instruments—if you've had instruments replaced, the panel repaired or altered, or the airplane's interior updated, confirm that all markings and placards are installed and correct.
e) Weight and Balance data: Be sure the Aircraft Equipment List is present and updated with any changes. Check that the Weight and Balance data is in the airplane and, if equipment was relocated, added or removed from the airplane, that old data has been signed off as "superceded" and that a new weight and balance sheet is enclosed and signed by the mechanic.
2) Pilot's Operating Handbook. Ensure the airplane's Pilot's Operating Handbook is intact and in the airplane.
3) Airworthiness Directives list. Double check that your most current AD list is in your possession.
4) Logbook entries. Check that your logbooks have been returned to you, and that:
a) Airplane, engine and propeller logs, as applicable to the work, have a signed statement listing all the work that was done. NOTE: Carrying the logs in the airplane, even to a repair shop, is not required in the U.S. It's common practice for a repair shop to give owners logbook information typed on a sticker, to be applied to the logbooks after the pilot flies home. In that case, ensure the sticker has been given to you, and affix it to the logs as soon as possible.
b) Return to service statement. There must be a signed statement in the logbooks returning the airplane to service. NOTE: sometimes you, the pilot, will make this log entry following a test flight.
c) All "yellow tags" for installed equipment are in the logbooks or in your possession.
d) Similarly, that all Form 337 field approvals and/or Supplemental Type Certificate papers are complete, signed, and in your possession.
5) Exterior Documentation. Especially if your airplane was painted or cleaned, check for the:
a) Registration number. It sounds odd, but on a bad day a paint shop might get your N-number wrong on one or both sides of the airplane.
b) Exterior serial number data plate. U.S. Customs requires the airplane serial number to be posted on the exterior of the airplane, on the tail or directly after of the wing.
c) Stickers. Other exterior stickers, like U.S. Customs fees stickers or state registrations, need to be reaffixed after painting, and may be inadvertently removed in an "aggressive" wash job.
d) Other placards. Confirm all other exterior lettering and placards are in place.
If the paperwork checks out (or while the shop is taking care of problems you've found), spend some time on a very thorough airworthiness check. Budget at least half an hour (an hour or more is better) to completely check the airplane after any work more complicated that a simple oil change. In addition to the usual preflight inspection items, check:
1) Primary flight controls. Check that all primary flight controls are:
a) Properly and securely attached, and that they;
b) Move freely and correctly with control movement.
2) Flaps. Confirm the flaps are:
a) Properly and securely attached, and that they;
b) Move freely when operated and stop at full "down" and full "up," and at intermediate positions where preselects are installed.
3) Trim tabs. Confirm that trim tabs are;
a) Securely attached and the hinge lines are unobstructed, and;
b) Properly aligned. Trim indicators in the cockpit may not correctly reflect actual trim tab position. Set the cockpit trim indicators to "zero," then check that the trim tabs are flush with the appropriate control surface, and;
c) Properly connected. Make sure trim tabs move in the proper direction when you move cockpit controls (manual, and electric if installed).
4) Landing gear. Be especially careful to inspect:
a) Tires and struts for proper inflation and condition.
b) Uplocks and downlocks for springs, bolts and cables.
c) Gear doors for proper installation and security.
d) Manual extension mechanisms. Make certain all required equipment is installed and accessible.
5) Access panels. Check allfor security, paying special attention to anything else that was likely removed in the shop.
6) Safety wiring. Confirm all required safety wiring is properly installed.
7) Fluids. Look for any leaks, drips or stains. Bring any signs of a leak to your mechanic's attention and get an explanation.
8) Generalfit and finish. Make certain seats and seat belts are properly installed. Ensure all equipment is in place and accessible.
9) "Stuff" . Make sure all items you left in the airplane (headsets, charts, flashlights, oxygen bottles, etc.) are where they're supposed to be. SUGGESTION: Take everything the mechanics won't need out of the airplane before leaving it at the shop to avoid the chance equipment will be misplaced or lost—and to help the mechanic keep his/her shop less cluttered with piles of your "stuff" during work.
In the best of worlds, you've been inspecting your airplane for at least an hour…and you haven't even started the engine(s). Next time, we'll look at what's perhaps the most important part of accepting an airplane from the shop—the post-maintenance test flight.
©2003 Thomas P. Turner for www.comanchepilot.com
Thomas P. Turner is a 3,300-hour ATP with over 2,100 hours as a CFI, and holds a Master's Degree in Aviation Safety. He contributes regularly to many aviation magazines, the American Bonanza Society journal, and www.ipilot.com. Formerly lead instructor for the Bonanza at Flight Safety, he served in the USAF, has worked as a production test pilot, ran a small FBO, and sold aviation insurance. An Oshkosh speaker and course developer for Embry-Riddle Aeronautical University, Tom's books include titles on "Cockpit Resource Management" and "Controlling Pilot Error," published by McGraw-Hill.