Pratt & Whitney Engines Need Borescope Checks for Rotor Clashes
Published Date: 9/17/2026
Proposed Rule
Summary
The FAA proposes to adopt a new airworthiness directive (AD) for all Pratt & Whitney (PW) Model PW1519G, PW1521G, PW1521GA, PW1521G- 3, PW1524G, PW1524G-3, PW1525G, PW1525G-3, PW1919G, PW1919G-RC, PW1921G, PW1921G-RC, PW1922G, PW1923G, and PW1923G-A engines with a certain high-pressure compressor (HPC) module installed. This proposed AD was prompted by six reports of clashing found on either the HPC 2nd stage rotor or 3rd stage rotor caused by contact with the corresponding HPC variable stator vanes (VSV). This proposed AD would require initial and repetitive borescope inspections (BSIs) of the HPC 1st stage, 2nd stage, and 3rd stage rotor rear rim surfaces for evidence of wear, scratching, or contact with the corresponding HPC VSV inner locating ring and, depending on the results, removal from service and replacement. This proposed AD would also require replacement of the HPC VSV bushing set as terminating action to the initial and repetitive BSIs of the HPC 1st stage, 2nd stage, and 3rd stage rotor rear rim surfaces. The FAA is proposing this AD to address the unsafe condition on these products.
Analyzed Economic Effects
4 provisions identified: 0 benefits, 4 costs, 0 mixed.
Mandatory VSV bushing set replacement
At the next HPC front case split flange separation after the AD effective date, you must replace the HPC variable stator vane (VSV) bushing set with parts eligible for installation. The FAA estimates replacement will take 1 work-hour plus parts, with a parts cost of $20,300 and a total cost per engine of $20,385 (FAA estimate). The FAA estimates 215 U.S.-registered engines are affected, totaling $4,382,775.
Expensive rotor replacements if damage found
If a BSI finds evidence of contact/damage, you must remove and replace the damaged HPC rotor(s) before further flight. The FAA lists estimated on‑condition total costs per engine of $316,050 for HPC 1st stage rotor replacement, $301,550 for HPC 2nd stage rotor replacement, and $258,950 for HPC 3rd stage rotor replacement (each includes labor and parts as shown in the NPRM).
Required initial and repetitive inspections
If your airplane has one of the listed Pratt & Whitney PW1500G or PW1900G engines with the affected HPC module serial numbers, you must do an initial borescope inspection (BSI) of the HPC 1st, 2nd, and 3rd stage rotor rear rim surfaces before accumulating 8,000 flight hours or within 1,000 flight hours after the AD effective date, whichever is later. After that, you must do repetitive BSIs at intervals not to exceed 1,000 flight hours.
Who must comply and who is excluded
This proposed AD applies only to the listed PW Model PW1500G and PW1900G engines that have an HPC module with serial numbers listed in Table 1 of the Pratt & Whitney Alert Service Bulletins dated July 13, 2026. The AD does not apply to engines that have already incorporated PW Service Bulletin PW1000G-A-72-00-0224-00A-930A-D or PW1000G-A-72-00-0170-00B-930A-D, as applicable.
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