Cardinal Spar Carry through NPRM

Summary and Analysis

On 5/11/2021 the FAA issued an NPRM, a Notice of Proposed Rulemaking related to the Cardinal spar carry through. That document can be found here.

The process invites comments from the public within the first 45 days. Those comments can be seen by all who visit the site to comment and will be read by the FAA.

You may access the comment system for this NPRM at this link.

There has been an ongoing discussion of this NPRM on the CFO Community at this link.

The following is a summary of my thoughts on this NPRM. Please do not directly copy these statements, as that may reduce their effectiveness.

I encourage you to review the documents and discussion and come to your own conclusions about those things which are important to you, then comment on those things. This will ring true and will give the FAA a true indication of our thoughts.

Comments on NPRM Docket No. FAA-2020-1078; Project Identifier AD-2020-00716-A:

¶ 39.13.g Visual Inspection within 12 months or 200 hours in operation

Mechanics are already busy and the required effort will add substantial time to an annual.

There are limited shops with the required experience and they are booked months in advance.

The prohibition of flight after an inspection failure encourages owners to inspect only at a facility which they would trust to complete repairs if needed.

The current shop and time capacity of capable shops is inadequate to provide the fleet with the required inspection and treatment within the 12 month period.

Recommendation: The requirement of 200 hours TIS alone should be sufficient to maintain flight safety. Zero Cardinals failures have occurred in over 50 years of fleet operation.

¶ 39.13.g.2 Evidence of previous blending requires removal from service.

This statement conflicts directly with (39.13.i) "Credit for previous actions."

Many spars have been blended within limits as advised by the Textron service letter or under the direct, documented guidance of Textron.

Some IAs have mistaken original factory blending as undocumented field corrosion removal.

Many mechanics will miss this statement from ¶ 39.13.g: "You are not required to inspect the lower cap to web radius, spar web, upper cap, or lugs." which seems to remove these areas from the visual inspection for previous blending. This focus on the critical lower spar flange is appropriate and appreciated.

"Evidence of blending" is judgmental, some IAs may consider a normal difference in surface texture to be such evidence.

No distinction is made between documented and undocumented prior work.

Recommendation: Remove this ambiguous statement in favor of the existing dimensional limits for blending.

¶ 39.13.g.4 Comply with (h) (eddy current) before further flight.

An aircraft successfully completing a visual inspection would be safer than an aircraft still within the compliance period which has not had a visual inspection.

Industry capacity would be increased if mechanics could remove the interior, perform the visual inspection, then fly to a provider for eddy current inspection and return for treatment and reassembly of the interior.

Recommendation: Remove the requirement "before further flight" from requirement (4). That would still require the eddy current testing to be done, but provide flexibility on where that step is completed.

¶ 39.13.m Special flight permits are prohibited.

As the designated work may be beyond the skills or equipment of local mechanics, this prohibition would leave even aircraft in excellent condition stuck at airports where this type of inspection is not available.

¶ 39.13.g.1 already addresses the grounding of aircraft where a crack is found.

Recommendation: Allow ferry flights after visual inspection where no cracks are found.

These pages are a collection of the ideas and impressions of the Cardinal pilots who frequent this site. This information is anecdotal, informal and may not be completely accurate. The Cardinal Flyers are not certified mechanics and do not guarantee the accuracy of the contents of these pages. Please research and confirm anything that is referenced on these pages with the experts appropriate to your situation.

As always, the aircraft maintenance, operations and flight manuals, the FAA and the advice of a certified mechanic and flight instructor, should be your primary sources of information regarding safe maintenance and operation of your aircraft.