It is the question every fighter pilot gets asked at a dinner party, and the one the US Air Force spent five years and a public innovation competition trying to answer properly. How do you go to the toilet when you are strapped into an ejection seat, wearing a parachute harness, a G-suit and a survival vest, eight hours from anywhere?

The honest answer, for most of the history of the jet fighter, has been: badly. And for one group of pilots it was worse than badly. It was a documented health problem that the service knew about, wrote about in its own contracting documents, and did not solve for three decades.

This is not a novelty story. It touches G-tolerance, harness discipline, retention, and at least one funeral.

The Piddle Pack, and Why It Is Harder Than It Sounds

The standard item is a piddle pack: a small sealed bag filled with absorbent gel that turns liquid into something that will not slosh. It holds roughly 500 millilitres. It costs almost nothing, needs no power, and has been in the inventory for decades.

Using one is the difficult part. Maj Justin “Hasard” Lee, an F-35 pilot with F-16 time, described the process for Sandboxx as being like driving a car while unwrapping a bag and urinating into it while staying in your lane and avoiding traffic, then amplifying that into three dimensions, just below the speed of sound, with someone potentially trying to shoot you down.

The seat itself does not help. The F-16 reclines roughly 30 degrees with separate leg holes, a design chosen to raise G-tolerance by shortening the vertical distance between heart and head.

It gets harder still with an anti-exposure suit on. Retired A-10 pilot Gregg Montijo has described the full-length rubberised suits worn over cold water as having a tiny zipper encased in rubber that had to be worked open before the pilot could urinate into the bag without getting wet or injured.

The Part That Killed People

The reason this is a safety subject rather than a comedy one is the harness.

Montijo has recounted a fatal accident on 17 January 2002. A friend of his, flying three sorties in a day with hot-pit refuelling between them, unfastened his parachute harness leg straps on the ground to use a piddle pack and did not reconnect them. Later in the flight he collided with another A-10. He ejected cleanly and separated from the seat. When the parachute opened, the harness came off his body because the leg straps were not connected, and he fell to his death.

The War Zone has reported that at least nine fatal crashes involving F-16s and an A-10 have been linked to male pilots dealing with piddle packs. Those individual accident reports are not something we have read ourselves, so treat the total as The War Zone’s count rather than an official tally. The mechanism, however, is not in doubt, and one anonymous F-15E pilot put the operational version of it plainly to Task & Purpose: there had been times when he was unstrapped and unzipped when a radio call came in for troops in contact.

Military Times filmed a female fighter pilot demonstrating the traditional method in 2020. It is the clearest available answer to the dinner-party question, and it explains without a word of commentary why the Air Force went looking for something better.

Tactical Dehydration Is a Real Term, and It Is in a Government Document

Faced with equipment that did not fit them, a lot of women stopped drinking.

The phrase for it is tactical dehydration, and the reason it belongs in a serious article rather than a locker-room one is that the US Air Force used it in its own 2020 solicitation for better relief hardware. That document states that many female aircrew resort to tactical dehydration to avoid the difficulties and potential dangers of relieving themselves in flight, and that dehydration lowers G-tolerance by up to 50 per cent while causing headaches, altered vision and reduced physical and cognitive performance.

Lower G-tolerance in a fighter is not an abstraction. It is the margin before G-induced loss of consciousness. Alex Dietrich, who flew F/A-18F Super Hornets in the US Navy, told Task & Purpose that dehydration affects everything from reaction time to vision, and that both of those matter rather a lot when landing on a ship at night.

How widespread was it? Task & Purpose, citing a 2023 survey published in Naval Safety Command’s Approach, reported that nearly 93 per cent of female pilots and aircrew surveyed at commands in California, Japan and Spain said they would tactically dehydrate, in some cases going without water on flights as long as eight hours. We have not read that survey ourselves, so the figure belongs to Task & Purpose’s reading of it.

One thing the evidence does pas support is the assumption that flying fighters wrecks women’s bladders. Fischer and Berg surveyed 274 US Air Force women on flying status for Obstetrics and Gynecology in 1999 and found a 26.3 per cent rate of urinary incontinence, statistically similar to the general population, with the type of aircraft flown making no difference at all. The problem was never the aeroplane. It was the kit.

Thirty Years of Nearly Working

US restrictions on women flying combat aircraft were lifted in April 1993, and Jeannie Flynn, later Lt Gen Jeannie Leavitt, graduated from F-15E training in February 1994 as the Air Force’s first female fighter pilot. The equipment took rather longer to catch up.

In 2008 the Air Force bought 300 Advanced Mission Extender Devices from Omni: a cup or pad under the flight suit, a hose, a battery pump and a bag. It was a genuine idea, and it landed in the field to mixed reviews. Dietrich called it over-engineered, like a vacuum, and quoted another aviator on the first-generation device running on six AAA batteries and being a giant pain.

Omni’s own instructional film for the female AMXDmax is the most concrete look at how a pump system is actually worn and pre-flighted, and it shows how many steps sit between a pilot and a device that was supposed to remove steps.

By 2021 the Air Force was fielding Skydrate, Omni’s later system, with what the service described as a larger collection bag, improved flow rate, multiple hose lengths, one-hand on-off operation and more interface sizes to account for anatomical differences. Thirty female aviators and nine pilots took part in the testing. Maj Nikki Yogi, an F-35A pilot who flew with the devices, said in the Air Force release that a pilot should be focused on taking the fight to the enemy rather than on whether the relief device is going to work.

Even then the physics lagged behind the anatomy.

It is worth saying that not everyone thinks the pumps were necessary. Trevor “Dozen” Aldridge, a former F-15C pilot who flew with the Thunderbirds, told Task & Purpose that for 99 per cent of missions piddle packs work just fine, and dismissed the new hardware as a typical modern acquisition that would cost more and deliver less. That view exists in the community and deserves airing, although it is also a view from a cockpit where the old kit already fit.

AFWERX, the Sky High Relief Challenge and AIRUS

In August 2020 the Air Force ran the Sky High Relief Challenge through AFWERX, the Air Force Research Laboratory’s innovation incubator at Wright-Patterson AFB. It asked for a urine collection system usable by women pilots on missions of up to 16 hours. The service framed it in retention terms, writing that addressing female-specific equipment and female aviators’ wellbeing was a top priority and that the outcomes would help improve retention, advance recruitment and eliminate gender gaps.

Eleven companies won. In 2022, two received prototyping contracts. One of them, Airion, delivered the Advanced Inflight Relief Universal System, AIRUS, which launched in January 2025 with new pilots in Air Force flight training receiving it first while operational units phase it in.

The specification reads like something designed by people who asked. Seven interface cups, five sized for women and two for men. A collection bag holding up to 1,800 millilitres, which Airion puts at four to seven uses. Dual-knit underwear as part of the kit. Testing across F-16, F-15, A-10 and F-35 fleets with aviators from first-assignment lieutenants to lieutenant colonels, and a finding from Air Combat Command’s Aircrew Performance Branch that the device did not hinder movement during critical flight manoeuvres.

The AIRUS system film shows the components laid out and worn. It is a small amount of hardware to have taken thirty years.

Pourquoi cela a-t-il pris autant de temps ?

The uncomfortable arithmetic is in the personnel numbers. In 2024 the Air Force was short 1,848 pilots and was manning only about 62 per cent of its fighter requirement. Of 10,964 rated pilots, 708 were women, about 6.5 per cent. A problem that affects a small minority of an already small community is a problem that is easy to leave for next year, every year.

That is the real story here, and it is not really about urine. It is about what happens when equipment is designed for the median user and everyone else is told to adapt. The pilots adapted. They MacGyvered adult nappies into zip-lock bags, had squadron equipment shops swap flight-suit zips for velcro, and, when none of that worked, stopped drinking water before a combat sortie.

Shelley Mendieta, who has worked the issue since her first deployment in 2003, told Task & Purpose that the AFWERX competition was a huge step and that the point was for the kit to become something aircrew are simply expected to have rather than something they have to fight for. Her summary of where things stand is the line to end on: this is the most positive she has seen the conversation in 25 years.

Sources: US Air Force Sky High Relief Challenge solicitation (2020), Air Force Materiel Command release (30 November 2021), Air Force Life Cycle Management Center (SJAFB in-flight bladder relief test), Task & Purpose (David Roza, December 2021; Patty Nieberg, April 2025), Sandboxx, Fischer JR and Berg PH, “Urinary incontinence in United States Air Force female aircrew,” Obstetrics and Gynecology, 1999;94:532-536, The War Zone, Defense News.