Harvards subject to new AD

By Adam Hunt

On June 8, 2005 the FAA issued an Emergency Airworthiness Directive (AD) on all Harvard-type aircraft, including all SNJs and AT-6s. The AD was issued as a result of the fatal crash of an SNJ-6 (AT-6F) which occurred on May 9, 2005 in the USA.

The cause of the accident was a large fatigue crack in the lower inboard wing attach angle causing wing separation. The aircraft had been used in a commercial aerobatic training and simulated air combat operation.

The FAA AD # 2005-12-51 grounds all the affected aircraft and requires a fluorescent penetrant inspection of all inboard and outboard, upper and lower wing attach angles, except for the nose angles of both wings for cracks. Any cracked angles are to be replaced prior to further flight. The fluorescent penetrant inspection is then to be repeated every 200 hours of flight time.

In response to the FAA AD on June 10, 2005 Transport Canada, issued Emergency Airworthiness Directive CF-2005-19 for Canadian built aircraft. The two ADs require the same inspections to be done on virtually all Harvard-type aircraft manufactured in either country.

The ADs both allow up to 10 hours of flight before July 8, 2005 for the sole purpose of moving the aircraft to a place where the inspection can be done. If the aircraft is flown to move it then the following restrictions apply: acrobatic maneuvers are prohibited, flight into known or forecast moderate or severe turbulence is prohibited, day VFR operation only and single pilot operation only - Passengers prohibited.

One of the key aspects to this Emergency AD is the results, whether any cracks are found or not, are required to be reported to TC via the Service Difficult Reporting (SDR) system. These reports can be submitted through the web-based Transport Canada

Web Service Difficulty Reporting System (WSDRS).

The information gained from these reports from all the inspections done will determine the next steps in the life of this AD.

COPA has held discussions with TC Continuing Airworthiness staff about this AD and its impact on aircraft owners. TC has indicated that they will work with COPA as the data comes in from the initial testing and decisions are made on future requirements.

It is very likely, if few or no cracks are found in the aircraft inspected, the AD may be amended to increase the time between repetitive inspections or eliminate them altogether. If many cracks are found then other measures may have to be employed.

If cracks are found only on aircraft used in certain flight profiles (aerobatics, racing, etc) than there may be different restrictions or requirements based on past or present aircraft use. This will only be known when the SDRs are submitted as each aircraft is tested.

At this point the early test results from the USA indicate the first few aircraft have passed with no cracks, including one aircraft that was raced at Reno for many years.

TC Continuing Airworthiness staff has indicated that due to the many different manufacturers of these aircraft and the many different models, the AD is far from perfect in capturing which aircraft need to have this inspection done.

Due to these factors TC is willing to look at proposals for any Alternative Methods of Compliance (AMOC) or substantiated request for alleviation of the requirements. This means, if you own one of the affected aircraft but believe it shouldn’t apply to your specific model or individual aircraft, then TC will seriously consider your application to not comply with the AD if you can show acceptable reasons why.

Applications for alleviation or AMOC should be addressed to Bill Miller, TC Continuing Airworthiness, Ottawa, 613 952-4388, fax 613 996-9178 or millerw@tc.gc.ca or any Transport Canada Centre.

COPA will be working with TC Continuing Airworthiness, the FAA and the aircraft type clubs involved with this AD as the data comes in and decisions are made on future revisions to the requirements for ongoing testing.