The company found that some production lots of the Cartridge Actuated Devices used in the ejection seats might be defective and therefore needs to be replaced.
Hundreds of military aircraft around the world have been grounded after ejection seat manufacturer Martin Baker discovered a potential defect in some production lots of the Cartridge Actuated Device (CAD), the explosive cartridges used to propel the seat out of an aircraft during an emergency. The ejection seats are now undergoing inspections to verify the absence of defects before allowing the aircraft to return to fly.
CADs initiate a series of automatic functions when aircrew pull the ejection handle to safely egress the aircraft and deploy the aircrews’ parachute. The CAD is inspected regularly, and replaced if needed, during period maintenance of the aircraft but can be affected by environmental and operational conditions.
The first to ground their aircraft were the British, which were grounded on July 22, 2022, a temporary precautionary measure, their Hawk T1 trainers assigned to the Red Arrows, and the Typhoon fighter jets involved in non-essential flying activities. The Red Arrows were cleared to resume flying on the same day, while the Typhoons returned to fly this week. Also on July 22, Germany temporarily suspended flight operations with their Eurofighters because of the same problem, while unconfirmed sources mention a possible grounding of the Tornados too.
On July 26 it was the turn of the United States, as NAVAIR disclosed that the potential defect of the CADs was also affecting the F/A-18B/C/D Hornet, F/A-18E/F Super Hornet, E/A-18G Growler, T-45 Goshawk and F-5 Tiger II. The press release specified that only aircraft equipped with CADs within a limited range of lot numbers are affected. The CAD are already being replaced at the aircraft’s assigned squadron and the aircraft will be inspected before its next flight.
The release also mentioned that, after being notified of the potential defect by Martin Baker, the team at Naval Surface Warfare Center Indian Head Division, which provides CADs/Propellant Actuated Devices (PADs) for Army, Air Force, Navy and Marine Corps aircraft, used validated radiography procedures to scan on-hand inventory to verify each item was properly manufactured before sending to the fleet to replace existing CADs.
The number of aircraft grounded as precaution is not specified. “Naval Air Systems Command has made the decision to ground some fixed-wing aircraft due to an ejection seat cartridge actuated device (CAD) production issue,” a Navy spokeswoman said in a statement to the press. “For operational security, we will not discuss the exact number of aircraft affected, but this issue does not affect every aircraft in Navy and Marine Corps inventory”.
A day later, on July 27, the U.S. Air Force grounded until further notice 203 T-38 Talons and 76 T-6 Texan IIs potentially affected by the CAD issue “out of an abundance of caution”. “We will not return aircraft affected by this issue to the flying schedule until we’re confident their escape systems are fully functional,” said Air Education and Training Command’s 19th Air Force commander Maj. Gen. Craig Wills. “Our instructor pilots accomplish an incredibly important and demanding mission every day, and we owe them safe and reliable aircraft.”
On July 29, the USAF Air Combat Command grounded the majority of its F-35As to inspect the ejection seats. “ACC’s F-35s do have Martin-Baker ejection seats, and on July 19, began a Time Compliance Technical Directive to inspect all of the cartridges on the ejection seat within 90 days,” stated ACC spokeswoman Alexi Worley. “Out of an abundance of caution, ACC units will execute a stand-down on July 29 to expedite the inspection process. Based on data gathered from those inspections, ACC will make a determination to resume operations.”
Later on the same day, the Air Education and Training Command also paused F-35 operations “to allow our logistics team to further analyze the issue and expedite the inspection process,” said AETC spokeswoman Capt. Lauren Woods. “Based on the results of these inspections and in conjunction with ACC, the lead command for F-35, AETC will make a decision regarding continued operations.”
Also on July 29, the Navy and Marine Corps admitted that they have quietly been inspecting their F-35B and F-35C fleets for some time to determine if they are impacted by the problem, with the Navy saying it completed inspections on July 26 and the Marines saying they completed over 90% of the inspections. Both services’ F-35 were not grounded, however, as a small number of CADs were determined to be potentially affected and were immediately replaced.
The F-35 Joint Program Office had previously issued an order to inspect all F-35s in a 90-day window as precaution. “The Department of the Navy decided to compress the 90-day inspection timeline to having each aircraft inspected prior to its next flight. All inspections are being conducted in an expedited manner with a high priority,” said F-35 JPO deputy spokesman Chief Petty Officer Matthew Olay.
On July 30, Israel also grounded its F-35I Adir fighter jets, after assessing the situation. “The Air Force received information about a safety finding in the ejection seats in the F-35 array that is assessed as low risk. In addition, a directive was received to carry out tests during the next 90 days,” the IDF said. In the meanwhile, operational flights will continue after being approved on a case-by-case basis.
We contacted Martin Baker for a statement about the issue and Steve Roberts, the company’s Head of Business Development, provided us more details:
“During a routine maintenance inspection at Hill AFB in April ’22, an anomaly was discovered with one of the Seat Cartridge Actuated Device (CAD) in the F-35 seat. This was quickly traced back to a gap in the manufacturing process which was addressed and changed. The F-35 Program introduced a one-time directive to inspect this CAD on all Seats in order to return the F-35 aircraft to flight.
This issue was found to be unique to this particular CAD part number and unique to the F-35, Martin-Baker has been providing the primes and multiple Govt agencies with supporting data to prove that all other aircraft may be excluded. Outside the F-35, not a single anomaly has been discovered worldwide as a result of the forensic investigation which continues at pace”.
So, even if multiple types of aircraft were grounded, it seems that the CAD production lots affected by the defect were possibly used only for the F-35’s Mk16/US16E ejection seat. Roberts provided some more details to Air Force Times, saying that the CAD’s “defective part was loose and missing the magnesium powder used to ignite the propellant that shoots someone to safety”.