A final FAA airworthiness directive, AD 2026-20-09, requires operators of certain Bombardier BD-700-2A12 (Global 7500) airplanes to correct low clearance at three places in the right wing and inspect for adequate clearance, to address a possible fuel tank ignition source in a lightning strike. FLEX AI™ does not measure clearances or inspect fuel lines and wiring, and it does not replace this AD or any check in it.
Three spots inside one business jet wing had less clearance than they should. Nothing broke. No system failed. The reports were of gaps that were smaller than the design intended, and the Federal Aviation Administration has now made closing those gaps mandatory across the U.S. fleet of the affected airplanes.
On October 14, 2026, the Federal Register published a final FAA airworthiness directive, AD 2026-20-09, for certain Bombardier, Inc. Model BD-700-2A12 airplanes, the type designation of the Global 7500. The rule takes effect November 18, 2026.
The directive traces back to Transport Canada, the aviation authority of the State of Design. Transport Canada AD CF-2025-49, dated October 1, 2025, reported low clearance at three locations in the right wing:
According to the FAA, these low clearance conditions, if not addressed, could result in an ignition source developing in the fuel tank in the event of a lightning strike. That is the reason a few millimeters matter here. Inside a fuel-carrying wing, the distance between a conductive fitting and a fuel line is part of how the airplane is protected when lightning finds it.
Nothing failed. The finding was a measurement, and the fleet is closing it under the AD.
The final rule (Federal Register Doc. 2026-21010, 91 FR 65100; Docket No. FAA-2026-2289; Amendment 39-23482; Project Identifier MCAI-2025-01592-T) follows a notice of proposed rulemaking published on March 4, 2026. It requires operators to comply with the actions and compliance times in Transport Canada AD CF-2025-49, with two exceptions: the FAA rule's own effective date replaces the Canadian one, and flight hours replace "hours air time." The reporting step in the Canadian material is not required.
As the FAA summarizes the incorporated material, the work is:
The FAA estimates that the AD affects 60 airplanes of U.S. registry. For the required actions it estimates 9 work-hours at $85 per hour, or $765 in labor, plus $1,928 in parts, for $2,693 per airplane and $161,580 across U.S. operators. If the on-condition bracket replacement is needed, the FAA estimates another 14 work-hours ($1,190) plus $4,582 in parts, or $5,772 per airplane, and notes it has no way to know how many aircraft will need it. According to the manufacturer, some or all of these costs may be covered under warranty.
By AD standards, that is a modest bill. The more interesting part of the rule is what the FAA said in response to public comments.
Five individuals supported the proposal without change. One commenter asked why the FAA had not issued an emergency AD, and whether the condition could contribute to fuel starvation or called for interim inspections or a shorter compliance time. The FAA's answers were direct. The low clearance condition would not contribute to fuel starvation, because there is no potential fouling of the fuel vent line and no effect on fuel system operation. The compliance times in the Transport Canada AD are adequate based on the manufacturer's risk evaluation. And, in the FAA's words, there is no system failure associated with this unsafe condition.
A second commenter asked the FAA to reopen the comment period over access to incorporated material and the basis for the cost estimate. The FAA declined and adopted the rule as proposed, apart from minor editorial changes.
That combination is worth noticing. A real unsafe condition, a mandatory fix, and no failure behind it. The system worked the way it is meant to: someone measured, found a gap below what the design intended, reported it, and the fix moved through two regulators into a rule.
Here is the part that stays with me. A clearance is checked on the ground, on one day, with the airplane at rest. The wing around that clearance flies every cycle. It bends under load, it carries fuel that shifts and cools, and it moves through temperature swings from ramp to cruise and back.
None of that makes the inspection wrong. A ground measurement against a defined limit is exactly the right tool for this kind of condition, and the AD is the right answer to it. But it does raise a broader question for any maintenance organization: when a problem shows up as a measurement rather than a failure, what else should you look at, and what do you know about how that structure behaved between the visits?
For most fleets, the honest answer is that the record between inspections is thin. You know what was found on the day. You know the flight hours and cycles. You usually do not have a continuous picture of what the structure actually lived through in service.
Business aviation maintenance teams are good at this work. They track ADs and service bulletins closely, they plan access to wing bays carefully because opening them is expensive, and they often bundle directive work with scheduled checks to limit downtime. Many will look at a rule like this one and ask whether the same access can be used to look at nearby installations while the panels are open. That kind of judgment is what keeps fleets safe, and no sensor replaces it.
FLEX AI™, from Platinum Eagle Aerospace, is built to collect and trend strain and temperature in flight, so the people responsible for an airframe have a record of what the structure experienced between inspections. The aim is to help move structural work into planned checks, with fewer surprises.
To be clear about scope: FLEX AI™ does not measure clearances, does not inspect fuel lines, hydraulic lines or wiring, and does not protect against lightning. It does not replace AD 2026-20-09 or any check in it, and it does not replace any airworthiness directive. Our FAA Supplemental Type Certificate is in process and will be finished before the end of 2026. Platinum Eagle Aerospace is ISO 9001 certified, and AS9100 certification is in process.
When a problem shows up as a measurement rather than a failure, how does your team decide what else to look at? I would like to hear how other operators approach it.
Source: Federal Register, "Airworthiness Directives; Bombardier, Inc., Airplanes," Doc. 2026-21010, published October 14, 2026, effective November 18, 2026 (AD 2026-20-09). This article summarizes a public regulatory document for general information and is not maintenance or compliance guidance. Always follow the AD and the approved manufacturer and Transport Canada material.
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