WASHINGTON — The two-seater EA-18G was cruising at 25,000 feet Jan. 29, about 60 miles south of Seattle on a flight from Washington State’s Naval Air Station Whidbey Island to Naval Weapons Station China Lake. The crew received a warning that the system that controls the cockpit air temperature and cabin pressure, known as the environmental control system, was icing.

By the time the flight was over, an elite aircrew with Air Test and Evaluation Squadron Nine was being rushed for medical treatment, and yet another failure of the EA-18G Growler’s environmental control system — one not seen in any of the previous physiological episodes linked to the ECS — was raising new concerns in the Navy’s sisyphean fight to stop physiological episodes from putting pilots at risk in the sky.

The temperature inside the cockpit suddenly plunged to temperatures reaching -30 degrees and a mist pumped into the the cockpit, covering the instruments and windows in a layer of ice, rendering the pilots almost completely blind, according to several sources familiar with the incident and an internal report obtained by Defense News.

The fog inside the aircraft iced over the instrument panel, forcing the pilot and electronic warfare officer to use a Garmin watch to keep track of their heading and altitude while air controllers began relaying instructions to the crew. The pilot and EWO were forced to use the emergency oxygen supply, which was completely depleted by the end of the flight.

A heroic effort by the two-person crew and the ground-based controllers managed to guide the aircraft back to Whidbey Island, but both pilot and EWO suffered serious injuries due to frostbite. The aircrew suffered from “severe blistering and burns on hands,” according to the Navy internal report.

In a statement, Naval Air Forces spokesman Cmdr. Ron Flanders confirmed the incident and that the Navy was trying to determine the cause of the incident.

“The aircrew was treated upon landing; one of the aircrew is already back in a flight status; the other is not yet back in a flight status but is expected to make a complete recovery,”

“The mishap is under investigation; I cannot comment further. Once the investigation is complete, the Navy will determine which further actions are necessary.”

Link

Well that's terrifying

Kudos to the crew. I can't imagine how tempting it must have been to take a chance on a Martin-Baker ride to get it over with.

I'm not sure I fully understand.....Why not simply descend into warmer air and then you wouldn't need supplemental oxygen either. ie: Descend to 2000 feet and fly home....

Odd...

quote:

Originally posted by mike28w:
I'm not sure I fully understand.....Why not simply descend into warmer air and then you wouldn't need supplemental oxygen either. ie: Descend to 2000 feet and fly home....

Odd...

Because the planes environmental control system (ECS) was stuck on uber-fricking cold. Emergency O2 was probably warmer that the -30 air in the plane.

quote:

The temperature inside the cockpit suddenly plunged to temperatures reaching -30 degrees and a mist pumped into the the cockpit, covering the instruments and windows in a layer of ice

I wonder if they considered jettisoning the canopy, then your suggestion (lower altitude) may have helped. Basically the A/C was on full blast with mist.

What I can’t imagine is why they didn’t make an emergency decent to warm, breathable air.

ETA: I see this was asked. I fly civilian jets for a living and can’t speak to the military jet but surely they have some emergency depress or other smoke removal procedure that would bring ambient air into the cockpit.

quote:

Originally posted by SigEd:
What I can’t imagine is why they didn’t make an emergency decent to warm, breathable air.

It wasn't the passive air temperature that was messing them up, it appears as though it was the plane's own version of AC that was icing the inside of the cockpit.

In short: the EA-18G's environmental regulation system went HAL 9000 on the aircrew.

quote:

Originally posted by RHINOWSO:

quote:

Originally posted by mike28w:
I'm not sure I fully understand.....Why not simply descend into warmer air and then you wouldn't need supplemental oxygen either. ie: Descend to 2000 feet and fly home....

Odd...

Because the planes environmental control system (ECS) was stuck on uber-fricking cold. Emergency O2 was probably warmer that the -30 air in the plane.

quote:

The temperature inside the cockpit suddenly plunged to temperatures reaching -30 degrees and a mist pumped into the the cockpit, covering the instruments and windows in a layer of ice

I wonder if they considered jettisoning the canopy, then your suggestion (lower altitude) may have helped. Basically the A/C was on full blast with mist.

I honestly don't see how it's possible for an airplane to have an environmental control system that can cool the interior of the plane that much that rapidly unless it's basically just pressurizing the inside of the plane with super-cold air from outside the plane.

A commercial deep freezer that uses a huge amount of power takes a long time to get that cold.

quote:

Originally posted by maladat:

I honestly don't see how it's possible for an airplane to have an environmental control system that can cool the interior of the plane that much that rapidly unless it's basically just pressurizing the inside of the plane with super-cold air from outside the plane.

A commercial deep freezer that uses a huge amount of power takes a long time to get that cold.

I don't understand either - aircrew are supposed to be able to depressurize the cabin and manually turn the ECS off.

The F-18 community has been plagued by some ECS issues for awhile now and this is honestly something they haven't seen before.

I also wonder if part of it is operating in the PACNW. F-18s have never been stationed there (or anywhere systemically cold and rainy), so maybe something over time is affecting the systems.

Granted allies have used legacy F-18s in cold locations, but the EA-18G is a different beast.

quote:

Originally posted by maladat:

quote:

Originally posted by RHINOWSO:

quote:

Originally posted by mike28w:
I'm not sure I fully understand.....Why not simply descend into warmer air and then you wouldn't need supplemental oxygen either. ie: Descend to 2000 feet and fly home....

Odd...

Because the planes environmental control system (ECS) was stuck on uber-fricking cold. Emergency O2 was probably warmer that the -30 air in the plane.

quote:

The temperature inside the cockpit suddenly plunged to temperatures reaching -30 degrees and a mist pumped into the the cockpit, covering the instruments and windows in a layer of ice

I wonder if they considered jettisoning the canopy, then your suggestion (lower altitude) may have helped. Basically the A/C was on full blast with mist.

I honestly don't see how it's possible for an airplane to have an environmental control system that can cool the interior of the plane that much that rapidly unless it's basically just pressurizing the inside of the plane with super-cold air from outside the plane.

A commercial deep freezer that uses a huge amount of power takes a long time to get that cold.

It’s very possible. The way environmental systems work is to take very high temp bleed air from the engines and run it through a type of heat exchanger that super cools it to a very low temp then add back a little bit of the hot air to make it usable and drain off the water that’s released. Probably the valve that rewarms the super cooled air failed. But there should still be ways to improve the situation. Again I can’t speak with authority on the systems available to them but a few things should have helped. Turning off the bleed air if they can control that. Lower power settings also could help. It’ll be interesting to see the outcome.

Also if your commercial freezer was jet powered it wouldn’ Take long.

.

The EA-18 is a variant of the F/A-18.

Mt. Rainier is also in that neighborhood. The article doesn't state if the EA-18 was over high terrain or not. Weather conditions, outside temperature, night or day flight, IFR or VFR, and other traffic all played a role in the decision making process.

I have no doubt the pilot descended as quickly as it was safe to do so.

If you read the full article, it is less about this specific incident and more about the failures in the environmental control system that have been encountered in the F/A-18 since 2010.

The article also briefly covered the Navy Instructor Pilot community that refused to fly the T-45 last April because they felt problems with the oxygen system (part of the environmental control system) was being ignored by the Navy.

In 2017, the Navy installed hyperbaric chambers aboard carriers to provide immediate treatment to pilots and they issued watches that measured cabin altitude pressure.

An newer Onboard Oxygen Generation System (OBOGS) was replacing the original F/A-18 system and the Navy began work on an updated model that was to replace the replacement in the future.

In the OP's linked article, is a link to this 2017 article about the reporting system the Navy put in place in 2010. It doesn't state the time frame, but I think these states are from 2010 thru June 2017 (www.DefenseNews.com/news/your-navy/2017/06/15/the-navy-s-30-day-review-reveals-few-answers-for-cockpit-air-problems/):

The Navy has investigated hundreds of reports of pilots experiencing physiological episodes. So far, 382 cases have been adjudicated concerning the F/A-18 alone, of which 130 involved some type of possible contamination, 114 involved an environmental systems control failure, 50 involved oxygen system failure, 13 involved a breathing gas failure, 91 involved human factors and 76 were inconclusive,

.

If you have to rely on your watch to maintain altitude and heading due to instrument icing, you cannot make changes in altitude quickly. We have 5000+ foot mountains all over the place that just kind come out of sea level.

quote:

Originally posted by SigEd:

quote:

Originally posted by maladat:

quote:

Originally posted by RHINOWSO:

quote:

Originally posted by mike28w:
I'm not sure I fully understand.....Why not simply descend into warmer air and then you wouldn't need supplemental oxygen either. ie: Descend to 2000 feet and fly home....

Odd...

Because the planes environmental control system (ECS) was stuck on uber-fricking cold. Emergency O2 was probably warmer that the -30 air in the plane.

quote:

The temperature inside the cockpit suddenly plunged to temperatures reaching -30 degrees and a mist pumped into the the cockpit, covering the instruments and windows in a layer of ice

I wonder if they considered jettisoning the canopy, then your suggestion (lower altitude) may have helped. Basically the A/C was on full blast with mist.

I honestly don't see how it's possible for an airplane to have an environmental control system that can cool the interior of the plane that much that rapidly unless it's basically just pressurizing the inside of the plane with super-cold air from outside the plane.

A commercial deep freezer that uses a huge amount of power takes a long time to get that cold.

It’s very possible. The way environmental systems work is to take very high temp bleed air from the engines and run it through a type of heat exchanger that super cools it to a very low temp then add back a little bit of the hot air to make it usable and drain off the water that’s released. Probably the valve that rewarms the super cooled air failed. But there should still be ways to improve the situation. Again I can’t speak with authority on the systems available to them but a few things should have helped. Turning off the bleed air if they can control that. Lower power settings also could help. It’ll be interesting to see the outcome.

Also if your commercial freezer was jet powered it wouldn’ Take long.

Interesting. I did some reading, and it seems like it's kind of a combination thing.

They take hot, high-pressure air from the compressor stage of the engine, then use a heat exchanger fed with ambient air to cool the high-pressure air a lot but still somewhat above ambient temperature (using cold air outside the plane to cool the engine bleed air), then let the high-pressure air expand, which cools it further (typical refrigeration cycle).

From what I'm reading, the system works well even when the ambient air is warm (e.g., on the ground) but to get to temperatures like -30 degrees, you really need very cold ambient air (e.g., to be at altitude or someplace super cold).

Yeah, can't just simply drop to a low/warm altitude when it is a) winter anyway, b) you are blind, and c) there are 14k mountain peaks in the region.

Flying by Garmin watch...talk about pucker factor!

Garmin has to capitalize on this in their next marketing campaign.

"Garmin - good enough to fly a Navy jet!"

Don’t laugh. I wasn’t flying a jet, but after I spent an hour in solid IMC, broke out on the ILS at ~1100’ and lost electrical about 30 seconds later, no radios, no nav, I became a huge fan of Icom handheld radios and Garmin GPS 90s that ran on their own batteries and fit in your shirt pocket.

It’s good to have when you have to make do with what you have.

My father had a somewhat similar experience with his instruments while flying a P-80 over the Rockies one dark night. Everything was fine until all his instrument lights went out leaving him in total darkness. He happened to have a penlight in his flightsuit pocket so he flashed it on every few seconds to read his gauges until he was able to land.

quote:

Originally posted by SigEd:
What I can’t imagine is why they didn’t make an emergency decent to warm, breathable air.

ETA: I see this was asked. I fly civilian jets for a living and can’t speak to the military jet but surely they have some emergency depress or other smoke removal procedure that would bring ambient air into the cockpit.

We used to get a condition in the C-130 via the air cycle machine that filled the aircraft with a mist under certain circumstances, and the vents would blow snow pellets. In the case of the growler crew, much smaller cockpit, everything iced up, no way to see instrumentation or out of the cockpit would have been problematic.

I ended up this summer in a smallish single engine airplane (16,000 lbs), flying for about 200 miles in heavy smoke, with very minimal instrumentation, and got very disoriented.

Sounds like these guys couldn't see past their helmet visor. Not good.

The environmental pack uses 600 degree air and cycles it through a cooling and expansion process, to mix again with other hot air bled off the engine, to regulate the environment...but is subject to condensation and freezing, and reference to what someone asked previously, it's not your grandfather's air conditioning unit.

Picture an air conditioner powered by a turbojet engine, and you're on the right track.

quote:

Originally posted by RHINOWSO:
I wonder if they considered jettisoning the canopy, then your suggestion (lower altitude) may have helped. Basically the A/C was on full blast with mist.

Flying a convertible Hornet (no canopy) at 150 KIAS to lower altitudes in the PacNW in the middle of winter? Or keep the canopy and deal with the cold air conditioning? That's a hell of a dilemma, and sure to cause the backseater "some discomfort" if the decision had been to blow the canopy.

According to the article these guys were from VX-9, the test and eval squadron out of China Lake so they weren't dumb-asses. Sometimes all the available choices really suck. Good on 'em for getting down in one piece.

quote:

Originally posted by Tailhook 84:

quote:

Originally posted by RHINOWSO:
I wonder if they considered jettisoning the canopy, then your suggestion (lower altitude) may have helped. Basically the A/C was on full blast with mist.

Flying a convertible Hornet (no canopy) at 150 KIAS to lower altitudes in the PacNW in the middle of winter? Or keep the canopy and deal with the cold air conditioning? That's a hell of a dilemma, and sure to cause the backseater "some discomfort" if the decision had been to blow the canopy.

According to the article these guys were from VX-9, the test and eval squadron out of China Lake so they weren't dumb-asses. Sometimes all the available choices really suck. Good on 'em for getting down in one piece.

Yeah, I hadn't really considered the weather at the time - out of the frying pan and into the fire really, -30 in the cockpit, getting frostbite, and everything frosting over. Ugh, it's gone from suck to blow.

They did well to get it back, no doubt. Honestly with all the ECS issues over the past couple years, I'm glad I'm out of the game.