Regulatory Brief -- FAA proposed twin Cessna wing spar ADs

Regulatory Brief

FAA proposed twin Cessna wing spar ADs

The issue:

On May 15, 2003, the FAA proposed two airworthiness directives mandating inspection of twin Cessna wing spar caps for fatigue cracks and installation of a Cessna manufactured spar strap modification kit. The proposed ADs affect twin Cessna 401, 402, 411, and 414A airplanes.

The importance to our members:

The proposed ADs affect more than 1,000 airplanes in the U.S. registry, and compliance estimates exceed 485 man-hours and $70,000 per airplane. The proposed ADs' compliance actions require highly specialized tooling and highly skilled technicians - as few as three twin Cessna maintenance facilities are currently capable of safely complying with the actions required by the two AD proposals. It will likely take years to complete the proposed ADs' compliance actions.

Most recent Web posting:

FAA issues twin Cessna wing spar ADs

The FAA Tuesday published "final rules" adopting new airworthiness directives (ADs) for most Cessna models 401, 402, 411, and 414 twin-engine aircraft. The ADs ( 2005-12-12 and 2005-12-13) supersede emergency ADs that required repetitive wing spar inspection - and possibly repair - for fatigue cracks. The ADs become effective June 22.

These new ADs eliminate repetitive inspections with the installation of a wing spar strap. Compliance times vary depending upon total time on the airframe, but most private owners will likely have up to 800 hours to comply. And once the strap is installed, owners gain another 5,500 to 12,000 hours (depending on the model) before another inspection is required.

"The FAA worked with the industry to ultimately come up with a solution that addressed the safety concerns while maintaining the utility of these aircraft," said Luis Gutierrez, AOPA director of regulatory and certification affairs.

The FAA had originally issued two expensive proposed airworthiness directives on these aircraft but withdrew the proposals after vehement objections from AOPA and major Cessna owner organizations.

The original ADs would have grounded most models in the 400 series of twin-engine Cessna aircraft while they underwent inspection and installation of a wing spar strap kit at an estimated cost of $75,000 per aircraft. Following an extended public comment period that included a two-day government/industry summit, the FAA decided to rethink its proposal.

AOPA worked closely with twin Cessna owner groups to fight the original ADs. As originally proposed, the ADs would have forced the simultaneous grounding of nearly 1,500 twin Cessnas as they waited for expensive repairs at the few shops qualified to do the work. In many instances, the repair would exceed the value of the aircraft.

The FAA had several public meetings last summer to review alternatives with the industry and owners and to come up with a strategy for continued airworthiness of the aircraft.

While the new ADs still require a wing strap, in the meantime the cost of strap installation has diminished significantly as shops gain experience.

The new ADs also stretch out the compliance times for many owners. An aircraft with 5,500 to 10,000 hours time-in-service, for example, can fly for another 800 hours before complying with the AD.

The ADs take effect next week, but the FAA will accept comments on them until August 3.

Significant provisions:

  • Proposed AD 2002-CE-05-AD affects Cessna 401, 401A, 401B, 402, 402A, 402B, 411, and 411A airplanes.
  • Proposed AD 2002-CE-57-AD affects Cessna 402C and 414A airplanes.
  • The proposed ADs require inspection of wing spar caps for fatigue cracks, repair or replacement of any cracked wing spars, and installation of a Cessna manufactured spar strap modification kit on each wing spar.
  • Compliance estimates exceed 485 man-hours and $70,000 per airplane, and it's estimated that fleet wide compliance may take more than 6 years.
  • FAA states the proposed ADs are "intended to prevent wing spar cap failure due to undetected fatigue cracks."
  • The FAA's AD proposals are based upon a federally funded seven-year Cessna engineering analysis. However, FAA has to date failed to respond to AOPA and industry requests for copies of the engineering data Cessna cites as the basis for required airworthiness action.
  • The comment period has been reopened. Comments are due to the FAA on or before April 5, 2004.
  • Send comments to: FAA, Central Region, Office of the Regional Counsel, ATTN: Rules Docket No. 2002-CE-05-AD or Rules Docket No. 2002-CE-57-AD, 901 Locust, Room 506, Kansas City, Missouri 64106.
  • FAA published SAIB CE-04-08, alerting owners to public meetings.

AOPA position:

AOPA strongly opposed the FAA's originally proposed ADs. AOPA expressed serious concerns regarding the highly technical nature of the spar strap installation procedure and argued that compliance with the provisions of the ADs as written may result in years of aircraft downtime or operational restrictions for affected aircraft.

Status:

  • On May 15, 2003 FAA proposed AD 2002-CE-05-AD and AD 2002-CE-57-AD.
  • On September 3, 2003 AOPA submitted requests for extensions to the comment periods of proposed ADs 2002-CE-05-AD and 2002-CE-57-AD.
  • On October 3, 2003, FAA published extensions for proposed ADs 2002-CE-05-AD and 2002-CE-57-AD.
  • On December 8, 2003, AOPA submitted comments for proposed ADs 2002-CE-05-AD and 2002-CE-57-AD.
  • On January 21, 2004, FAA published SAIB CE-04-08 alerting owners to public meetings to be held on March 3 and 4 at the Hilton, Washington Dulles Airport in Herndon, Virginia.
    • There is no admission fee or other charge to attend or participate in this meeting.
    • The meeting is open to all who requested in advance to present or who register on the day of the meeting. This is subject to availability of space in the meeting room.
    • FAA representatives will conduct the meeting.
    • They will have a panel of technical experts and managers to discuss information on the subject.
    • The public meeting is intended as a forum to:
      • Resolve questions that concern the approach used in our determination that AD action is necessary; and
      • Seek additional data and supporting methodologies from industry, the general public, and operators.
    • The meeting will allow the public to present additional information not currently available to FAA and an opportunity for FAA to explain the methodology and technical assumptions that support their conclusions.
    • FAA experts, industry, and public participants are expected to hold a full discussion of all technical material presented at the meeting. If you present conclusions on this subject, you must submit data that supports your conclusions.
    • The FAA is also seeking information about possible corrective actions other than those in the proposed ADs. All submitted data will be part of the Rulemaking Dockets.

03/11/04 Public Meeting Notes

  • The FAA presented its evidence for pursuing two proposed twin Cessna airworthiness directives during a two-day meeting between the agency and those affected by the ADs.
  • The data made a strong case for potential structural problems with the twin Cessnas' wing spars and went far in justifying the agency's decision to move forward with development of the directives.
  • The meeting also demonstrated the FAA's growing concern about the aging general aviation fleet and hinted at the broader future use of engineering models to pinpoint areas of concern and possible remedial action.
  • The FAA has agreed to reconvene a second meeting with updated proposals based on this meetings discussions.
  • The FAA has agreed to not issue the ADs until after the next meeting, barring any accidents between now and then.

04/20/04 Industry Survey

  • AOPA, the Cessna Pilots Association, Cessna Twin Spar Corp., Cessna Owners Organization, Twin Cessna Flyers, and Regional Air Cargo Carriers Association create a Web site to collect fleet data and distribute relevant reference materials.
  • The data gathered in this survey will help convince the FAA that the proposed compliance times for Part 91 airplanes should not necessarily be defined by the engineering analysis performed by Cessna that looked specifically at 402s in commercial service and supported by six or seven actual aircraft, all of which were Cessna 402s in commercial service.

05/26/04 The FAA Withdraws Costly Twin Cessna AD Proposals

  • The FAA has withdrawn expensive proposed airworthiness directives against 400-series twin Cessna aircraft.
  • The FAA intends to reissue the ADs after alternative solutions have been developed. The FAA is also planning a second public meeting later this summer to review the alternatives with industry and owners and to come up with a strategy for continued airworthiness of the aircraft.

07/22/04 The FAA to Hold Second Public Hearing

  • FAA will hold the second of two hearings on fatigue cracking in wing spars of 400-series Cessna twin-engine aircraft.
  • The hearing will start at 8:30 a.m. on August 18 at the Kansas City Marriott Downtown in Kansas City, Missouri.

08/23/04 Twin Cessna Hearing - Kansas City

  • The FAA will be issuing a notice of proposed rulemaking (NPRM) by the end of the year, with an AD coming out by mid-2005.
  • The AD will be phased in over about a five-year period. For some of the lower-time owner-flown aircraft, the AD will likely not become applicable for many more years.
  • The data supports that there is a cracking issue in the 402 and 402A models; for the rest of the fleet, we're still looking at statistical engineering predictions, rather than actual field experience.
  • The FAA indicated that it is willing to consider well-engineered alternate means of compliance (AMOC) to remedy the problem and seemed to be prompting the assembled owners, owner's group representatives, and other interested parties to come up with additional solutions for the upcoming AD. Agency engineers said they would consider both physical and inspection alternatives.
  • The FAA's outline of the new NPRM for the airworthiness directive departs from the fixed-date compliance times that were part of the first NPRM.
  • The new FAA proposal for tip-tank twins such as the 401, 401A, 401B, 402, 402A, 402B, 411, and 411A models would require installing a wing spar strap kit in aircraft with more than 6,500 hours time in service. Airplanes that have more than 18,000 airframe hours would have to comply with the AD as soon as it is issued. Airplanes with 12,000 to 18,000 airframe hours would have to comply at 200 flight hours after issuance; 10,000 to 11,999-hour airplanes would have 400 hours, and all lower time airplanes would have 800 hours to comply.
  • For 402C and 414A (late model version) airplanes, the AD would kick in at 15,000 hours. Owners with more than 20,000 hours would have to comply within 500 hours of the issue date of the AD; 18,000 to 19,999-hour airplane owners would have 1,000 hours to comply, and 15,000 to 17,999-hour airplane owners would have 1,500 hours to comply.
  • For 414A (earlier model version) airplanes, the AD would apply at 9,000 hours. Compliance with the AD will be required in accordance with a phased-in schedule (TBD) similar to the one proposed for the other affected models.

02/20/05 Emergency AD 2005-05-51 Issued for Cessna 402C, 414A Models

  • On Sunday, February 20, the FAA issued an emergency AD (2005-05-51) requiring frequent repetitive wing spar inspections on all Cessna 402Cs and many Cessna 414As.

03/02/05 Emergency AD 2005-05-52 Issued for Cessna 402C, 414A Models

  • This AD supersedes emergency AD 2005-05-51, which superseded AD 2000-23-01. Requires visual inspections for all Model 402C airplanes with fewer than 15,000 hours total time-in-service (TIS): Initially inspect upon accumulating 10,000 hours TIS on the airplane or at the next inspection that would have been required by AD 2000-23-01 or emergency AD 2005-05-51, whichever occurs later. Repetitively inspect thereafter at intervals not to exceed 110 hours TIS until accumulating 15,000 hours TIS.

UPDATE: 06/14/05 FAA issues final ADs 2005-12-12 and 2005-12-13 affecting most Cessna 401, 402, 411, and 414 models

  • These ADs supersede AD 2005-05-52 and AD 79-10-15 that required repetitive wing spar inspection - and possibly repair - for fatigue cracks. The new ADs eliminate repetitive inspections with the installation of a wing spar strap. And once the strap is installed, owners gain another 5,500 to 12,000 hours (depending on the model) before another inspection is required. The ADs becomes effective June 22. The FAA must receive any comments on these ADs by August 3, 2005.

Related documents:


Updated Thursday, June 16, 2005 12:06:12 PM