Lockheed Martin F-35 Lightning II Joint Strike Fighter (JSF)

[Ronny]

I don't quite get it. How come the air used for cooling is not available to drive the turbine?. Isn't it supposed to pass through the fuel-air heat exchanger then still go into the turbine, just slightly hotter?.
Also if I understand correctly, this method of using engine air seem to generate much higher cooling capacity compared to the traditional ambient air scope right?. The air flow is obviously higher because the engine such air in?.
I recalled the cooling capacity of the big F-15E is only around 35kW, so for the medium size F-35 to have 30 kW cooling from its engine alone seem quite impressive. Then it probably get another 5-10 kW of cooling through the top left side cooling scope for a total of 40kW cooling
View attachment 677792
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The F135 has a very sophisticated integration of the engine and airframe cooling systems with the fan duct coolers, IPP airflow, and ECS systems. Bleed air from the high compressor is pre-cooled by cooler fan bypass air before it leaves the engine into the airframe systems. Hot air from airframe systems is routed to other under fan duct heat exchangers to be cooled by fan bypass air under certain operating conditions, but not all. At high power settings, the fan bypass air is well over 400F, making it too hot to cool any ECS air. All of this airflow out and into the fan duct coolers is controlled by the ECS system with multiple valves to ensure cooling is achieved.

But the point missed is that air bled from the compressor at high pressure leaves the engine, that pressure being used by various IPP/ECS components to make cooling happen in the airframe. After that, the bleed air is at low pressure and cannot rejoin the engine high pressure core flow, and is exhausted overboard, lost to cause of making thrust.

Wait a second, so if I understand you correctly, not only the air from the low pressure stage of the engine (the fan stage) is used for the cooling of the aircraft. But also the air from the high pressure compressor (the core) is used for cooling?. Isn't that a bit counter productive?. And why don't they use the fuel to take heat from the avionic/airframe, then flow the fuel into the heat exchanger for cooling (you know like a computer cooler). Isn't that a lot more efficient since liquid conduct heat much better? what the point of taking air from the engine into the airframe and not the other way around aka pumping fuel over hot stuff then into the heat exchanger inside the cool section of the engine


Another thing, I thought that only the vent on top of the body is used for avionic cooling and the belly vents are for engine and airframe cooling? (I vaguely remember reading that on Codeonemagazine)
But from what you explained earlier, both top side and belly side vents can be used for both function: avionic cooling and airframe cooling?

 

[Ronny]

Nevertheless, I still think F-35 cooling capacity is pretty insane if it can get 30 kW from the engine integrated fuel air heat exchanger alone. With an additional 5-10 kW cooling from the top body vents, it seem pretty competitive even when compare to something like F-15EX

 

[rooster]

I don't quite get it. How come the air used for cooling is not available to drive the turbine?. Isn't it supposed to pass through the fuel-air heat exchanger then still go into the turbine, just slightly hotter?.
Also if I understand correctly, this method of using engine air seem to generate much higher cooling capacity compared to the traditional ambient air scope right?. The air flow is obviously higher because the engine such air in?.
I recalled the cooling capacity of the big F-15E is only around 35kW, so for the medium size F-35 to have 30 kW cooling from its engine alone seem quite impressive. Then it probably get another 5-10 kW of cooling through the top left side cooling scope for a total of 40kW cooling
View attachment 677792
View attachment 677793

The F135 has a very sophisticated integration of the engine and airframe cooling systems with the fan duct coolers, IPP airflow, and ECS systems. Bleed air from the high compressor is pre-cooled by cooler fan bypass air before it leaves the engine into the airframe systems. Hot air from airframe systems is routed to other under fan duct heat exchangers to be cooled by fan bypass air under certain operating conditions, but not all. At high power settings, the fan bypass air is well over 400F, making it too hot to cool any ECS air. All of this airflow out and into the fan duct coolers is controlled by the ECS system with multiple valves to ensure cooling is achieved.

But the point missed is that air bled from the compressor at high pressure leaves the engine, that pressure being used by various IPP/ECS components to make cooling happen in the airframe. After that, the bleed air is at low pressure and cannot rejoin the engine high pressure core flow, and is exhausted overboard, lost to cause of making thrust.

Wait a second, so if I understand you correctly, not only the air from the low pressure stage of the engine (the fan stage) is used for the cooling of the aircraft. But also the air from the high pressure compressor (the core) is used for cooling?. Isn't that a bit counter productive?. And why don't they use the fuel to take heat from the avionic/airframe, then flow the fuel into the heat exchanger for cooling (you know like a computer cooler). Isn't that a lot more efficient since liquid conduct heat much better? what the point of taking air from the engine into the airframe and not the other way around aka pumping fuel over hot stuff then into the heat exchanger inside the cool section of the engine
View attachment 677804

Another thing, I thought that only the vent on top of the body is used for avionic cooling and the belly vents are for engine and airframe cooling? (I vaguely remember reading that on Codeonemagazine)
But from what you explained earlier, both top side and belly side vents can be used for both function: avionic cooling and airframe cooling?

View attachment 677805
View attachment 677806

Roger on the vents cooling function. What ever happened to the heat issues with the two weapons bays?

 

[Vanessa1402]

Yes, the F135 is supplying 30kW of bleed flow for 3F. However, this requires the engine to run hotter and faster to offset this diversion of core airflow, which reduces hot section life, driving the power module back to depot sooner than planned.

Do you have additional source for that or it come from your experience working on these engine?.
Anyway, I find this pretty interesting since F-18E/F intended to provide 15kW liquid cooling for APG-79. Given that APG-81 has a bit more T/R modules than APG-79 (1626 modules vs 1368 modules), I wonder what the cooling requirement for APG-81 would be. Maybe 19-20kW?

View attachment 677766

39 years as a Customer Support / Field Service Engineer for P&W

Taking bleed air from the core airflow is a double penalty for engine performance. All of the air taken from the compressor has absorbed turbine power to get it pressurized - this lost turbine power has to be offset by pushing more fuel and temperature into the combustor. And this air is no longer available to drive the turbine, which means further fuel and temp increase. And the impact is increased at altitude where air density is lower but the cooling demands remain relatively constant.

This increased bleed flow pushes up the operating temperatures throughout the flight envelope. The engine performance is reduced when against the max operating limits, and the temperatures are increased at all other operating conditions, cumulatively using up available hot section life.

I don't quite get it. How come the air used for cooling is not available to drive the turbine?. Isn't it supposed to pass through the fuel-air heat exchanger then still go into the turbine, just slightly hotter?.
Also if I understand correctly, this method of using engine air seem to generate much higher cooling capacity compared to the traditional ambient air scope right?. The air flow is obviously higher because the engine such air in?.
I recalled the cooling capacity of the big F-15E is only around 35kW, so for the medium size F-35 to have 30 kW cooling from its engine alone seem quite impressive. Then it probably get another 5-10 kW of cooling through the top left side cooling scope for a total of 40kW cooling
View attachment 677792
View attachment 677793

The F135 has a very sophisticated integration of the engine and airframe cooling systems with the fan duct coolers, IPP airflow, and ECS systems. Bleed air from the high compressor is pre-cooled by cooler fan bypass air before it leaves the engine into the airframe systems. Hot air from airframe systems is routed to other under fan duct heat exchangers to be cooled by fan bypass air under certain operating conditions, but not all. At high power settings, the fan bypass air is well over 400F, making it too hot to cool any ECS air. All of this airflow out and into the fan duct coolers is controlled by the ECS system with multiple valves to ensure cooling is achieved.

But the point missed is that air bled from the compressor at high pressure leaves the engine, that pressure being used by various IPP/ECS components to make cooling happen in the airframe. After that, the bleed air is at low pressure and cannot rejoin the engine high pressure core flow, and is exhausted overboard, lost to cause of making thrust.

sorry for my dumb question but what is bleed air and how is it different from ram air and bypass air?

 

[Cannonfodder43]

Bleed air is pressurized air from the compressor stages that is tapped or "bleed" for use in other work applications.

 

[F119Doctor]

sorry for my dumb question but what is bleed air and how is it different from ram air and bypass air?

Ram Air - outside air brought onboard the airframe using forward facing scoops

Bypass Air - On a turbofan engine, pressurized fan discharge air that bypasses around the engine core via the bypass ducts and goes directly to the engine exhaust to make thrust

Bleed Air - Pressurized air taken from the engine compressor flow and sent to the airframe for cockpit pressurization and airframe systems heating / cooling. You can have bleed air taken from the back end of the core compressor only (example F-15/F100 13th stage bleed)), from the middle of the compressor (F-16/F100 switches from 13th stage bleed at low power to cooler 7th stage bleed at high power), and/or from fan bypass air (F-16/F100-229 bleeds fan duct flow to an airframe heat exchanger to pre-cool the 7th / 13th bleed air before it enters the ECS system).

 

[F119Doctor]

The F135 has a very sophisticated integration of the engine and airframe cooling systems with the fan duct coolers, IPP airflow, and ECS systems. Bleed air from the high compressor is pre-cooled by cooler fan bypass air before it leaves the engine into the airframe systems. Hot air from airframe systems is routed to other under fan duct heat exchangers to be cooled by fan bypass air under certain operating conditions, but not all. At high power settings, the fan bypass air is well over 400F, making it too hot to cool any ECS air. All of this airflow out and into the fan duct coolers is controlled by the ECS system with multiple valves to ensure cooling is achieved.

But the point missed is that air bled from the compressor at high pressure leaves the engine, that pressure being used by various IPP/ECS components to make cooling happen in the airframe. After that, the bleed air is at low pressure and cannot rejoin the engine high pressure core flow, and is exhausted overboard, lost to cause of making thrust.

Wait a second, so if I understand you correctly, not only the air from the low pressure stage of the engine (the fan stage) is used for the cooling of the aircraft. But also the air from the high pressure compressor (the core) is used for cooling?. Isn't that a bit counter productive?. And why don't they use the fuel to take heat from the avionic/airframe, then flow the fuel into the heat exchanger for cooling (you know like a computer cooler). Isn't that a lot more efficient since liquid conduct heat much better? what the point of taking air from the engine into the airframe and not the other way around aka pumping fuel over hot stuff then into the heat exchanger inside the cool section of the engine
View attachment 677804

Another thing, I thought that only the vent on top of the body is used for avionic cooling and the belly vents are for engine and airframe cooling? (I vaguely remember reading that on Codeonemagazine)
But from what you explained earlier, both top side and belly side vents can be used for both function: avionic cooling and airframe cooling?

View attachment 677805
View attachment 677806

Relative to avionics cooling, yes to all of the above

The F-22 has liquid cooled avionics, where a PAO fluid is circulated through the black boxes to remove heat from the electronics. Other airframes have air cooled avionics where ECS air is circulated to remove the heat. I don't know what the F-35 uses, but probably both. That heat has to flow from high temperature to a low temperature heat sink unless you have something like a heat pump to move the heat to a higher temperature sink.

Fuel is used for multiple cooling functions - engine oil system, airframe hydraulics, avionics cooling. Ultimately, that waste heat is used in the engine when the heated fuel is burned. But there are limits on how hot the fuel can get before it starts breaking down and forming coke deposits inside the fuel passages within the engine. If the fuel gets too hot due to the heat rejection going into it, you have to find another place to cool the fuel, such as a ram air heat exchanger that may not work well on the ground or under high ambient air temperatures. The fuel in the tank is a constantly reducing level as it is consumed, reducing the total fuel heat sink capability later in the flight. And ram air means scoops, which impact RCS signature and airframe drag.

When you run out of fuel cooling capacity, bleed air become the next cooling source. While bleed air can be very hot, it is also high pressure. This pressure can be used to run an air cycle machine, which essentially turns that hot, high pressure air into cool low pressure air that is used for cockpit pressurization and avionics cooling, either directly with air cooling or with a heat exchanger for liquid cooling. The used cooling air is then dumped overboard, taking the heat with it. The F135 fan duct heat exchangers do help pull heat out of the system, making the cooling more effective, and heating the bypass air actually increases engine thrust, at least partially offsetting the aero drag of the heat exchangers.

But, the higher the cooling requirements, the greater the bleed air mass flow requirements, and the bigger the impact on engine operating temperatures and hot section life.

 

[GTX]

The F-22 has liquid cooled avionics, where a PAO fluid is circulated through the black boxes to remove heat from the electronics. Other airframes have air cooled avionics where ECS air is circulated to remove the heat. I don't know what the F-35 uses, but probably both.

The F-35 uses a combination of air, PAO and fuel as cooling fluids.

 

[F119Doctor]

The F-22 has liquid cooled avionics, where a PAO fluid is circulated through the black boxes to remove heat from the electronics. Other airframes have air cooled avionics where ECS air is circulated to remove the heat. I don't know what the F-35 uses, but probably both.

The F-35 uses a combination of air, PAO and fuel as cooling fluids.

And in case anyone asks, PAO is Poly Alpha Olifin (spelling?) synthetic fluid that is very stable and a good heat transfer medium.

 

[NeilChapman]

Well if there is another war (big war) in Europe, the B is a better choice than the C because Britain's runways will be smoked. The performance penalty over the C isn't that much of a difference to matter

How? Considering that Russia has failed to close the runways of even the Ukranian Air Force? Barring nukes, it's very hard to see how Russia has the wherewithal to mount an effective offensive counterair campaign that far beyond its borders. And if nukes come in, who cares what version of F-35 you have?

You're thinking of the wrong war. Think island hopping and you'll understand why the F35B is their choice.

 

[Vanessa1402]

Relative to avionics cooling, yes to all of the above
The F-22 has liquid cooled avionics, where a PAO fluid is circulated through the black boxes to remove heat from the electronics. Other airframes have air cooled avionics where ECS air is circulated to remove the heat.

Do you mean F-22 has no cooling air vents to let air in?.

When you run out of fuel cooling capacity, bleed air become the next cooling source. While bleed air can be very hot, it is also high pressure. This pressure can be used to run an air cycle machine, which essentially turns that hot, high pressure air into cool low pressure air that is used for cockpit pressurization and avionics cooling, either directly with air cooling or with a heat exchanger for liquid cooling.

Pardon my stupidity again but what exactly is air cycle machine and how can it turn the very hot bleed air to cool air?.

 

[Forest Green]

You're thinking of the wrong war. Think island hopping and you'll understand why the F35B is their choice.

Falklands.

 

[F119Doctor]

Relative to avionics cooling, yes to all of the above
The F-22 has liquid cooled avionics, where a PAO fluid is circulated through the black boxes to remove heat from the electronics. Other airframes have air cooled avionics where ECS air is circulated to remove the heat.

Do you mean F-22 has no cooling air vents to let air in?.

When you run out of fuel cooling capacity, bleed air become the next cooling source. While bleed air can be very hot, it is also high pressure. This pressure can be used to run an air cycle machine, which essentially turns that hot, high pressure air into cool low pressure air that is used for cockpit pressurization and avionics cooling, either directly with air cooling or with a heat exchanger for liquid cooling.

Pardon my stupidity again but what exactly is air cycle machine and how can it turn the very hot bleed air to cool air?.

The F-22 does use fuel for cooling various airframe systems and engine bleed air for ECS pressurization and cooling. It also utilizes inlet boundary layer diverter air as a source for system cooling.

Wikipedia lookup for air cycle machine:
https://en.wikipedia.org/wiki/Air_cycle_machine

 

[GTX]

And in case anyone asks, PAO is Poly Alpha Olifin (spelling?) synthetic fluid that is very stable and a good heat transfer medium.

Close - Polyalphaolefin

 

[NeilChapman]

You're thinking of the wrong war. Think island hopping and you'll understand why the F35B is their choice.

Falklands.

Perhaps, I was thinking of a possible future war in a different ocean.

 

[TomcatViP]

The single largest military construction contract on record in the Air Force database was awarded to build Tyndall Air Force Base up to be the Base of the Future.

Wednesday, Tyndall officials announced the U.S. Army Corps of Engineers (USACE) awarded a $532 million construction contract to Hensel Phelps to deliver 11 projects that will directly support flightline operations for the F-35A Lightning II aircraft. The jets are expected to arrive at Tyndall in September 2023. Officials say accounting for contingencies and contract oversight, this represents a $604 million investment in rebuilding Tyndall.

We’re told the Air Force Civil Engineer Center’s Natural Disaster Recovery Division is leading the rebuild. It is part of the Air Force Installation and Mission Support Center enterprise.

Officials say this will support the 325th Fighter Wing and their F-35 Program Integration Office. The flightline facilities will directly support the wing and its new F-35 mission.

“The rebuild gives us the unique opportunity to reimagine how we accommodate the needs of the F-35,” Col. Travis Leighton, NDR division chief, said. “We’re leveraging cutting-edge technology to increase cybersecurity and perimeter defense, enhance base safety and equip Airmen to execute the missions of today and tomorrow.”

https://www.wctv.tv/2022/05/11/record-contract-awarded-f-35-facilities-tyndall-air-force-base/

 

[TomcatViP]

Swiss leaning toward more cooperation with NATO is obviously a trend that only has been reinforced by them choosing the F-35:

https://www.reuters.com/markets/eur...leans-closer-nato-response-russia-2022-05-15/

What was that song saying?... No woman no cry

 

[TomcatViP]

Greece move forward on its plan to acquire some F-35:

“We will launch the process for the acquisition of a squadron of F-35 aircraft, and we do hope to be able to add this fantastic plane to the Greek Air Force before the end of this decade,” Mitsotakis said at the White House.

He also noted Lockheed Martin — which produces F-35s and F-16s — “officially expressed its interest in investing in Hellenic aerospace” last week, right before his visit to Washington.

Media outlets in Greece cited Greek government officials as noting Lockheed Martin has invited Athens to join the F-35 co-production program.

https://news.yahoo.com/greece-seeks-join-f-35-001400566.html

 

[TomcatViP]

Switzerland gov announces it will sign F-35 deal (36) without further delay (a referendum, potentially blocking the deal, was to take place before):

The Swiss government will sign a contract by the end of March to buy 36 Lockheed Martin F-35A Lightning II fighter jets, it said on Wednesday, pressing ahead without waiting for a referendum on the $5.5 billion deal.

https://news.yahoo.com/swiss-sign-deal-buy-f-132611960.html

 

[TomcatViP]

“Adversary Air” companies are no longer able to provide a worthwhile opponent to Air Force fighters at Nellis Air Force Base, Nev., and the Joint Pacific Alaska Range Complex (JPARC) Alaska, so Air Combat Command is letting contracts lapse and working toward creating a permanent F-35 Aggressor capability.

“What we’re finding, now … is these contracts aren’t very effective at Nellis at the high-end training environment,” Lt. Gen. David S. Nahom, deputy chief of staff for plans and programs, told the Senate Armed Services Committee on May 17. “What they provide is not giving us what we need.”

https://www.airforcemag.com/nahom-f...t-nellis-and-jparc-contract-adair-not-enough/
(The Great airfraft bazaar hence served no purpose. Those planes could have had a higher strategic role in the Ukraine crisis scenario.)

 

[TomcatViP]

(hijacked from a link posted by @bobbymike :

20000$ per flight hours !!! That would like reaching furtivity also in the DoD budgetary lines.

The cost-per-flight-hour for an F-35A amounted to $37,000 in 2019, and Lockheed aims to bring that down to $30,000 per hour by fiscal 2023. However, Lockheed Chief Finance Officer Jay Malave stated during the conference today that “we still think there’s runway to reduce it by another 35%” if the government signs onto a performance-based logistics deal.

Taiclet pointed out that Lockheed can’t drive down costs all on its own. Lockheed is responsible for about 40% of the sustainment costs associated with the F-35, with engine-maker Pratt & Whitney responsible for 10% and the services accountable for the rest.

“What I’ve proposed and have been proposing for a year — and now that we have an undersecretary for acquisition and sustainment in place, I think we’re going to get it finally — is a joint effort to put everybody in a room that can actually address the total cost base for the program,” he said, adding that the F-35 enterprise is currently running “inefficiently.”

https://breakingdefense.com/2022/06...onic-wind-tunnel-but-says-dod-isnt-buying-in/

 

[GTX]

(hijacked from a post by @bobbymike :

20000$ per flight hours !!! That would like reaching furtivity also in the DoD budgetary lines.

I would be cautious making any comments re cost per flight hour without seeing the actual breakdown.

 

[GTX]

800+ delivered!!!

https://www.f35.com/content/dam/lockheed-martin/aero/f35/documents/F-35_Fast_Facts_06_2022.pdf

 

[TomcatViP]

Next participating air force should be the Swiss one, with their gov anticipating signing the deal in the coming weeks.

 

[icyplanetnhc (Steve)]

https://www.thedrive.com/the-war-zo...-f-35-aggressors-dedicated-to-chinese-threats
The Aggressor F-35A is sporting a rather interesting splinter pattern reminiscent of some J-20 patterns.

 

[aonestudio]

https://www.nellis.af.mil/News/Arti...ates-at-nellis-with-aggressor-force-of-f-35s/
https://www.thedrive.com/the-war-zone/israel-has-extended-the-range-of-its-f-35s-report

 

[NMaude]

The Aggressor F-35A is sporting a rather interesting splinter pattern reminiscent of some J-20 patterns.

Probably not a coincidence.

 

[Manuducati]

https://www.nellis.af.mil/News/Arti...ates-at-nellis-with-aggressor-force-of-f-35s/
https://www.thedrive.com/the-war-zone/israel-has-extended-the-range-of-its-f-35s-report

Talking about the second article and how the Israelis were able to extend the range, beside the mentioned possibilities of jettisonable fuel tanks and conformal fuel tank, what about a possible extra tank filling one of the two weapons bay? Zero impact on stealth, drag or aerodynamic, leaving "only" one 2000lb bomb and one AIM-120 for self defense tho.

 

[NMaude]

I suspect that the Israeli extended range option is to enable the F-35 to strike at targets in Iran.

 

[siegecrossbow]

https://www.thedrive.com/the-war-zo...-f-35-aggressors-dedicated-to-chinese-threats
The Aggressor F-35A is sporting a rather interesting splinter pattern reminiscent of some J-20 patterns.

J-20 doesn't use the splinter pattern anymore. They are now using F-22 style camo.

 

[GTX]

800+ delivered!!!

https://www.f35.com/content/dam/lockheed-martin/aero/f35/documents/F-35_Fast_Facts_06_2022.pdf

Just a photo emphasise the point :

 

[Manuducati]

New pictures...

 

[siegecrossbow]

New pictures...

one of them carries luneburg lens while the other does not. Interesting.

 

[Tuna]

one of them carries luneburg lens while the other does not. Interesting.

Isn't there another possible mounting point on the other side, which wouldn't be visible from this angle?

 

[eagle]

You can see both sides of the aircraft in those two pictures. One of the F-35s is not carrying the lenses while the other one has the usual 4. Wouldn't make much sense otherwise.

 

[siegecrossbow]

one of them carries luneburg lens while the other does not. Interesting.

Isn't there another possible mounting point on the other side, which wouldn't be visible from this angle?

Look at the second photo. Both F-35s are facing the camera at the same angle. Lunesburg lens is visible on the one further away. There is no way that the vertical slab could’ve obscured it.

The below image shows it clearly.

 

[helmutkohl]

now that we have more pics and angles
looks more like their imitating Russian camo rather than the J-20s

 

[TomcatViP]

the agreement, struck with the Joint Program Office in April, “covers the base production and option quantities for up to 518 (maximum quantity) engines and equivalents with a contract value, if all options are exercised, of approximately $8 billion. Engine deliveries are set to begin later this year through the end of 2025.”

The award funds:

108 F135-PW-100 engines for the Air Force’s F-35As.
29 F135-PW-100s for the Navy/Marine Corps’ F-35Cs
26 F135-PW-600 engines for Marine Corp F-35Bs, which include the lift fan element unique to that variant.

https://www.airforcemag.com/raytheons-pratt-whitney-gets-4-4-billion-f-35-engine-deal/

 

[TomcatViP]

Would Canada revert into buying Gripens?

The Canadian government picked the F-35 in March as the preferred bidder for its next fighter jet, announcing plans to buy 88 of the fifth-generation aircraft. Deliveries would be slated to start in 2025.

However, the final contracts with Lockheed Martin have not been signed as negotiations are ongoing, and according to Global News, Procurement Minister Filomena Tassi has warned that it is not guaranteed that a deal will be reached. Canada’s history with the F-35 is a fraught one.

https://www.airforcemag.com/brown-v...arts-to-talk-arctic-norad-modernization-f-35/

 

[FighterJock]

Would Canada revert into buying Gripens?

The Canadian government picked the F-35 in March as the preferred bidder for its next fighter jet, announcing plans to buy 88 of the fifth-generation aircraft. Deliveries would be slated to start in 2025.

However, the final contracts with Lockheed Martin have not been signed as negotiations are ongoing, and according to Global News, Procurement Minister Filomena Tassi has warned that it is not guaranteed that a deal will be reached. Canada’s history with the F-35 is a fraught one.

https://www.airforcemag.com/brown-v...arts-to-talk-arctic-norad-modernization-f-35/

Here we go again.