I agree wholly with the poor maintenance and its a disgrace that a "temporary" repair was allowed to stay on the aircraft for 22 years.
As for the SSID being able to cover, that is exactly the point. Up to now, none of the OEM SID's address modified structure. All of the PSE inspections are for green aircraft only. In fact, depending on the OEM, some SID PSE inspections only cover a very specific location (even down to 3 or 4 fastener holes). Some of these philosophies assume that the most critical location will crack first and therefore inspecting it will safely cover the remainder of the area. NOT SO. Also, for the pre amendment 45 aircraft with SIDs, there is no FAA requirement at all to even do damage tolerance for anything other than the physical PSE location and most ADs on SIDs dont even mention a requirement for assessing the impact of repairs to PSEs.
Anyways, the fuselage pressure boundary repair assessment rule that went into effect in 2002 (FAR 121.370) has thresholds for doing the assessment. However, depending on the airline, it may or may not have been completed at this point. In fact, note taht the rule went into effect the same year China Airlines crashed. Maybe if it hadnt taken 14 years since Aloha to get the rule passed......
Also, the intent of the fuselage pressure boundary RAP was always intended as just a first step trying to address the structure with the most numerous repairs. Repairs to wing spars, engine mounts and flap tracks are just as critical. It shouldnt take a wing flying off (in the case of the Cessna 410 and the C130A firefighter) to convince people of this.
I have seen several hundred service related fatigue cracks in my years of experience and in almost every case the cracks could certainly have been either detected by DTA based inspections or avoided by placing a life limit on the component. All repairs should be required to meet the same level of safety as the baseline structure. No self respecting DER would ever have approved the China Airlines repair for DTA. Also, from what I know, the repair was only approved as "temporary" (ie time limited) which is only a "recommend approval" for any DER which also means it should have been approved by the cognizant FAA ACO. Unfortunately, prior to this rule, there is little requirements for tracking the status of any permanent or "temporary" repair. That is left up to the operator.
The new rule I believe will be a significant improvement. Other than the DTA requirement, it places a mandatory inspection of all repairs. If anything else, each one will get a very close inspection by an FAA inspector. Remember, many but not all operators still believe "if it aint broke dont fix it". (and if the doubler covers up the damage, oh well) Also, not all repair stations are created equally. So at least this will require a physical inspection. The issue at this moment is how to phase this requirement into the fleet.
Just as a final thought, how long should we really allow aircraft to fly? The answer is - As long as their safety is ensured. Many old aircraft never even had a fatigue test. I dont know about you, but as much as I like B17s, I still wouldnt want one crashing thru my roof.(did you note the AD issued just a couple of years ago by Seattle ACO to all B17 aircraft for mandatory mods to the wings due to chronic fatigue cracking?)
One of the upcoming rules includes establishing a Limit of Validity. Basically this is the equivalent of a 2 lifetime fatigue test divided by a scatter factor of 2. This LOV would limit the operation up to that point until an extended fatigue test or substantial analysis and component testing could be completed to establish a new LOV. Essentially this would ensure a service life up to LOV without widespread fatigue cracking.
As for the link with the US, the FAA considers all accidents in their evaluations. In fact, when an accident occurs overseas but involves a US manufacture aircraft, most of the time the local version of the NTSB will notify and forward all information to the cognizant FAA ACO. And in almost every case, the FAA will contact the OEM and inititate an investigation due to the possible impacts to the US operated fleet. By the way, the JAA/EASA is in the process of adopting a similar version of the FAA Aging Safety rule but even more stringent from what I hear.
James Burd
