The U.S. Air Force (USAF) is welcoming back its second female F-35 joint strike fighter pilot. A certain weight restriction introduced due to safety concerns prevented pilots from flying the jet for several years. With new modifications on the aircraft, the restrictions have been lifted and USAF’s second female pilot is now cleared to fly the jet.

In October 2015, the managers of the F-35 program restricted pilots under 136 lbs. from flying after discovering problems with the design of the Martin Baker US16E pilot escape system and the weight of the F-35 helmet. The flaws posed “an unacceptable risk of neck injury during parachute deployment/opening for lighter-weight pilots [in that weight range] at low-speed conditions,” Popular Mechanics reports.

The USAF and F-35 contractors have now fixed the issue by integrating new modifications into the aircraft – a lightweight switch to delay the deployment of the main parachute and a head support panel between the parachute risers to protect the pilot’s head during parachute opening.

So far, it is reported that eight aircraft at Luke Air Force Base in Arizona have been upgraded with a new ejection seat designed to accommodate lightweight aircrew. As a result, pilots weighing 103-245 lbs. are now cleared to fly the jet, allowing the unnamed female to begin training.

In fact, the weight restriction was already officially lifted in March 2017, but was delayed due to difficulties incorporating the modified equipment into the fighter’s fleet management system, the Autonomic Logistics and Information System, Aerospace Daily reported back in September, 2017.

Popular Mechanics writes that it will take until 2019 to complete the fixes on the 200 early versions of the F-35 currently flying worldwide. The new aircraft ordered in 2017 will have the safety modifications already installed into the jets.

The first female F-35 pilot, Lt. Col. Christine Mau, a former F-15E Strike Eagle pilot and deputy commander of the 33rd Fighter Wing Operations Group, began training on the F-35 in May 2015, at Eglin Air Force Base in Florida, but has recently retired from the USAF.  Back then, the event signified several milestones – it was the first woman to fly an F-35 anywhere in the world, demonstrating the increasing integration of female combat pilots into flight operations.

In November 2017, the Israel Air Force (IAF) reached a similar milestone by appointing a female fighter jet pilot as deputy commander of a combat squadron. The unnamed officer, an F-15 navigator, is to serve in the Spearhead Squadron, which flies F-15 fighter jets out of Tel Nof Airbase in central Israel, The Jerusalem Post reported at the time. This makes her the highest ranking woman in the IAF so far.