Most mechanics that I have talked with about this small part of the total SID inspection agree that this disassembly and re-assembly of the areas described would involve at least 80 to 120 man-hours. Additional time for the eddy current specialists to complete their inspection of the pressure bulkheads would be required. Any repairs that are found necessary would of course extend the downtime. A complete teardown and rebuild of the interior upholstery would be required. Priced a headliner lately? The total cost of the whole SID inspection would far exceed the value of some of the aircraft! Get the idea?
Some report that the time required for the complete SID inspection would be tantamount to an extensive airline C or D check. Some have estimated three to four months to complete the inspections assuming no major repairs are performed! Total labor cost alone is estimated at beyond $100,000. The average shop could not even attempt these inspections simply because it would tie up maintenance crews for too long on one aircraft. Specialty shops will be needed to do nothing but the SID work on the 400 Series.
In addition to the pressure cabin SID, there are numerous other disassembly and inspection requirements that will add hundreds of man-hours to the work required.
Can owners and operators afford all this?
Ever since a 737 lost part of its upper fuselage some years ago there has been an inordinate focus by manufacturers and the FAA on corrosion and structural failures. Never mind that this accident aircraft had been hauling fish drenched in salt water around the western Pacific and was exposed to corrosion for years.
Many have privately mentioned that manufacturers have finally hit on a way to sell new airplanes and get rid of the older ones.
In a recent publication the FAA stated: "The General Aviation fleet is being used well beyond the flight hours and years envisioned when the airplanes were designed. There is concern that continued airworthiness safety matters will become more common as the fleet ages. These airplanes could develop serious age-related problems as they continue to be used well beyond their design life . . ."
Best Practices Guide For Maintaining Aging General Aviation Aircraft, September 2003
It does not take much to see where the manufacturers and the FAA are going with this.
Based on the described engineering analysis and some reports from the field, the FAA (Cessna) has determined that additions to already existing AD's are necessary.
The FAA has published AD 79-10-15R2, which requires repetitive inspections of the right and left wing spar lower cap areas for fatigue cracks on the Model 401, 402, and 411 Series aircraft and mandates wing spar cap repairs where necessary.
402C and 414A aircraft have a similar design to the above aircraft so Cessna decided that it would add AD 2000-23-01, in November 2000 to include the Model 402C and require repetitive inspections of the forward, aft, and auxiliary wing spars for cracks. The Model 414A was not included at that time.
Now it will include extensive eddy current inspections on both the 402C and 414A Series aircraft.
In addition, on May 15, 2003, the FAA published NPRM 2002-CE-05-AD and 2002-CE-57-AD that is designed to require owners and operators of models 401, 402, 411, and 414 aircraft, all models, including wet wings, to reinforce their lower spar caps by installation of a spar cap strap kit. It is estimated that this will cost anywhere from $60,000 to $70,000.
These modifications are only a beginning. Over the next two years the FAA (Cessna) intends to require that the whole fleet of both 400 and 300 Series aircraft be modified in accord with this proposed AD. Is the single engine fleet next? Probably not .
Buyback? Class action lawsuits?
Now, to many operators of these aircraft this seems like a wholesale redesign of the whole fleet of Cessna workhorses. Some have even suggested that Cessna should buy back those aircraft that are not economically logical to modify or continue to operate. Insurance companies will probably refuse to insure such aircraft without proof of modification. Needless to say, the lawyers are looking very carefully at the situation because of the large number of people and aircraft concerned. Many have suggested a class action lawsuit to demand that Cessna pay for these modifications or buy back the aircraft concerned.
Spar straps are nothing new. Some early Beech King Airs were similarly equipped by STC. The problem here is the number of aircraft impacted and the costs associated vs. the current value of the fleet. It will just not be practical to modify a large number of the affected aircraft.
There has been much opposition to this proposed AD from all of the operator groups with little if any response, so far, from Cessna or the FAA. All are requesting that the comment period be extended so that the economic impact can be explored further, among other reasons.
The proposed AD's were designed by Cessna to address what it perceived to be a failure threat. Indeed, the studies performed by Cessna that back up this engineering change, were funded in large part by the FAA. But, the fact is there does not appear to be a significant threat of failure of the wing spars with these aircraft. According to reports, there has only been one accident involving a wing spar that was damaged in the Cessna factory during original manufacture of the aircraft. This was further aggravated by a landing accident that tore the landing gear off the aircraft! Little wonder that the wing failed some 18 years later! So far, this is the only documented failure.
More work for technicians?
Some have suggested that all these regulatory requirements will provide windfall work for technicians well into the future and provide a need to expand the workforce at many facilities. Could be, but the more logical result will be a reduction in the fleet size and a proportional reduction in work because of the maintenance costs involved. We'll just have to wait and see. When you have the time take a look at the SIDs and the AD's and see if you agree with me and others. Send comments to email@example.com.
Stephen P. Prentice is an attorney whose practice involves FAA-NTSB issues. He has an Airframe and Powerplant certificate and is an ATP rated pilot.