MQ-25 US Navy Stingray Program

[element1loop]

3:15 - General Atomics claims that their aircraft will more than double the strike range of the carrier air wing; that's pretty impressive considering that Lockheed's promo video said their Stingray would boost a fighter's combat radius by about 50%.

OK, but "strike range" is different to "combat radius", depending on weapon used. If they mean LRASM on SH, they could be more or less correct, even if fuel off-load was approx the same from all MQ-25 offerings. Grain of salt I think.

[zero-one]

Okay so why is the intake there again??

http://www.thedrive.com/the-war-zone/19 ... nker-drone

Comments by the author:

Flush inlet designs like this are notoriously problematic, especially during flight at elevated angles of attack—such as when landing aboard an aircraft carrier. Boundary layer airflow can also be a major issue, and separating it from the fuselage to provide stable, high volume air to the engine throughout the aircraft's flight envelope would seem to be highly problematic with such a design.

Just last week, Boeing announced that the engine used for their MQ-25 competitor is the Rolls Royce AE3007N
the same proven powerplant that is used on the RQ-4 Global Hawk and MQ-4C Triton.
Yet those high-flying unmanned aircraft provide a much more generous air intake to provide airflow to their AE3007s than what Boeing has devised for their MQ-25

A variant of the 9,000lb thrust class engine is also used on the Citation X and the Embraer 145. It's worth noting that General Atomics' entrant into the MQ-25 contest will be powered by the Pratt and Whitney PW815 turbofan that will be configured to generate 16,000lbs of thrust. How exactly Boeing intends on getting away with 43% less thrust while accomplishing the same mission is puzzling, but General Atomics does say they built extra margin into their design. Still, that's a big and peculiar thrust differential.

[KamenRiderBlade]

Is there anyway that Boeing can modify the fairings for the existing pod to be more "Stealthy / LO"? If the bloody pod is going to be stuck hanging outside due to requirements, wouldn't it make sense to give it a little bit of "Stealth Shaping / RAM coating?"

[KamenRiderBlade]

Okay so why is the intake there again??

I can only assume for LO reasons.
It wasn't going to be on the bottom where ground radar can see it's reflection.
It wasn't going to be on the sides or in front where it could potentially reflect something back while refueling.
All that was left was the top where something flying high and above "Might" see a reflection due to a perfect angle matching which is unlikely.

[zero-one]

It wasn't going to be on the bottom where ground radar can see it's reflection.
It wasn't going to be on the sides or in front where it could potentially reflect something back while refueling.
All that was left was the top where something flying high and above "Might" see a reflection due to a perfect angle matching which is unlikely.

I'm Worried about performance,
They're using a weaker engine, they are restricting the airflow (specially when landing) and they still need to carry 14,000 lbs of gas to give, 500 nm away.

What if they were not able to give the gas away and need to land under heavy weather conditions.

[element1loop]

I'm Worried about performance,
They're using a weaker engine, they are restricting the airflow (specially when landing) and they still need to carry 14,000 lbs of gas to give, 500 nm away.

What if they were not able to give the gas away and need to land under heavy weather conditions.

I included this on the previous page.

Military AE 3007H
Thrust: AE 3007H: 9,500 lbs
Bypass Ratio: 5

That's not just a 'high-bypass' turbofan, that's a very high-bypass turbofan.

Bypass that high does this; 5:1, which is to say, for every six packets of air entering the fan, only 1 packet (16.6%) is combusted in the core to drive the fan.

It is a ducted fan engine, driven by a small turbine.

The high speed fan then pushes out the rest of the unburned air (83.3%) through the outer-core duct.

Sound familiar?

It should be, as basically the AE 3007H will be as thrust responsive as a turboprop at low altitude, and low speed, in hot conditions.

In other words, it'll have much safer margins, due far better thrust and speed control than a typical mil jet engine on approach or departure.

It burns just 16.6 % of incident air, so is that much less prone to breathing combustion difficulties to keep that big efficient fan turning with plenty of speed, to both suck in the needed core air, and blast out the remainder like a large ducted turboprop.

High bypass engines, even near 3:1 ratio, are known for their characteristic high thrust and added stability at slow air and ground speeds.

I'm fairly confident Boeing got this inlet geometry right given they already completed low and high thrust ground testing, which no doubt included wind tunnel simulated high AOA approach, at edge of envelope for ISA and flight conditions.

[Dragon029]

OK, but "strike range" is different to "combat radius", depending on weapon used. If they mean LRASM on SH, they could be more or less correct, even if fuel off-load was approx the same from all MQ-25 offerings. Grain of salt I think.

I'm not certain that's what they meant by strike range (being a trade-show floor interview, people misspeak), but regardless, using that definition of 'strike range', an % increase in strike range is more valuable than an equal % increase in combat radius.

Let's say a Rhino has a 450nmi combat radius and the LRASM reaches out another 300nmi for a 'strike range' of 750nmi.

If we increase the combat radius of the Rhino by 1.5x to 675nmi, the 'strike range' has then become 975nmi, which is only 1.3x greater than the previous 750nmi.

Or to flip it around; if we're increasing the 'strike range' by 2x instead, we go from 750nmi to 1500nmi. Take away the 300nmi from the weapon's engagement range and you have a combat radius of 1200nmi, which is 2.67x greater than the original 450nmi.

Remember, General Atomic is proposing an aircraft powered by an engine that's roughly twice as powerful as both Boeing and Lockheed's engine choices. It might not be as low-drag as the other 2 proposals, but I fully expect it to carry considerably more fuel than its competitors; it'll certainly be interesting to see what it's spot factor is (though certainly GA have made it meet threshold requirements in that regard; it does feature both folding wings and empennage).

As for Boeing and their inlet design, I'd assume for LO reasons as well, although if they've engineered it well (and I think it's fair to assume they will have) it could also reduce drag and overall fuel efficiency. During approach I'd also note that those chines around the fuselage will help prevent flow separation and will help feed the inlet. As Kamen said though; even if they wanted a recessed intake for reduced drag, having one on the bottom still would have been better if LO wasn't a concern.

As for making stealthy pylons, AAR pods, etc, I don't see much point; keep the "MQ-25A" as a basic tanker / slightly LO ISR platform and make a follow-on MQ-25B that has structural modifications for proper LO / VLO (more swept wings for Boeing / GA, redesigned inlets, better fuselage shaping for Lockheed / GA, internal weapon / utility payload bays, etc).

[element1loop]

Boeing also claims to carry way more fuel than the required 14,000 lb, @ 500 nm radius, plus they plan to further widen and thicken their existing inboard wet-wing. While LM intimates they can just thicken their wing design, as required. So I don't see a capacity advantage here. A higher performance engine, for a larger heavier jet, also means a much higher fuel flow rate, so, grain of salt.

I read this last night, a very interesting bit of text which indicated LO perfornance and LO potential of a tanker family may become more important.

Future of Air Tanking: The Perspective of the 86th Wing Commander

04/11/2018

Robbin Laird

“The future of a large tanker will be to support more distributed and dispersed operations and we will be looking at small tactical refuelers providing fuel to tactical air combat assets – these tactical assets will likely be cheaper, unmanned and more expendable.

“That is where A3R comes in.

“I see an advantage in the automatic boom because it reduces the workload on the operator who in the future may be managing or controlling formations of UAV during AAR.

“As we learn to use this technology, it will be part of shaping the skill sets to transition to the next phase, of a large tanker replenishing smaller, automated tactical refuelers.”

Another aspect of change associated with KC-30A is part of the evolution within the battlespace as seen by Group Captain Pesce.

Namely, the proliferation of communications and sensor technology throughout the air combat force will include larger platforms such as C-17 and KC-30A, by including new SATCOM and other linkage technologies.

This is designed to support not only a dispersed force but also provide network redundancy in a disrupted and contested EM spectrum.

https://sldinfo.com/2018/04/the-kc-30a- ... commander/

So, automated RAAF rear of fight boom-tanking, of a small automated drone tanker, with a podded hose basket? Or does this foreshadow another small tactical drone-tanker, but with a boom, for RAAF and USAF use, with F-35As?

Attritable tactical drone auto-tankers ... wow ... decentralised/distributed with more backup comms for degradation redundancy.

We're not in Kansas any more..

[forbin]

The last official strike range of the F-35A was listed as 669nmi in the FY2018 SAR. The F-35C's range in that same SAR was still TBD. Hopefully, the FY219 SAR (which has already been leaked to some news orgs but not published) will set an actual number (yes, I have already filed a FOIA request).

fyi, The F-354A's 760nmi range was in A2A mode which is considerably lighter than it's A2G mode.

Previous numbers right now more reliable for CR with only internal fuel ofc
F-35A 1080 or 1090 km new 1240 *
F-35B 830 km 935 km
F-35C 1110 km 1240 km

do a big difference 10+ % new reliable now ?
*https://fr.scribd.com/document/375751665/JSF-Selected-Acquisition-Report-FY19-2017

These new was yet published last year in FY 2018 President budget

How many with 2 Fts of 1612 l surely 150 - 200 km in more

Exist a special topic for range especialy ?



About futur embarked tanker there are completely different and much more limited than true tanke KC-135* or other thay can add some fuel but few in more F-35 host 8.9 tons !

The Navy's goal for the aircraft is to be able to deliver 15,000 lb (6,800 kg) of fuel total to 4 to 6 airplanes at a range of [i]500 nmi (580 mi; 930 km)
https://en.wikipedia.org/wiki/MQ-25_Stingray[/i]

F/A-18E/F host 6.8 and 6.3 tons

* Total 92 tons 17 tons transferable to 2000 kms the max to short range seems 68 tons ? other common tankers host 70 -160 tons about 2/3 transferable dépends distance Chinese H-6U is the less capable with only 36 tons, 18.5 transferable

USN had before
KA-3 with 13 tons the total in general refueled to 460 mn
KA-6D with 11.7 tons in 1990's 4 by CAW
F/A-18E/F host 12 tons with 4 FTs

So a MQ-25 with IIRC 6.8 tons don't refuel completeley a F-35C ... in fact he refuel in part some F-35C

For embarked tanker numbers in futur Sqn with 12 and about 10 + for training, in reserve USN have 9 CAW do about 6 by Sqn which can refuel 4 F-35C a flight or in part 50 % about 9 almost a Sqn or 6 or 12 F/A-18E/F

[Corsair1963]

Personally, I would like to see Boeing win the T-X Advanced Trainer and Lockheed Martin the MQ-25A Contests. Just saying...

[sferrin]

Personally, I would like to see Boeing win the T-X Advanced Trainer and Lockheed Martin the MQ-25A Contests. Just saying...

I'd swap that.

[Corsair1963]

The Boeing T-X is more advance and likely cheaper to operate overall than the T-50 based trainer from Lockheed Martin. In addition the Lockheed Martin MQ-25A Flying Wing is more Efficient and Stealthier than the Boeing Model. So, personally I'll stick with my choices...

[zero-one]

How exactly is Boeing's T-X more advanced?

[Corsair1963]

Boeing T-X is an all-new aircraft designed specifically for the U.S. Air Force training mission.

Boeing’s design takes advantage of the latest technologies, tools and manufacturing techniques. It is an advanced aircraft designed to evolve as technologies, missions and training needs change.

The design is more affordable and flexible than older, existing aircraft.

“Our T-X is real, ready and the right choice for training pilots for generations to come,” said Boeing Defense, Space & Security President and CEO Leanne Caret.

The Boeing T-X aircraft has one engine, twin tails, stadium seating and an advanced cockpit with embedded training. The system also offers state-of-the-art ground-based training and a maintenance-friendly design for long-term supportability.

https://www.boeing.com/features/2016/09 ... 09-16.page


https://www.defensenews.com/breaking-ne ... -aircraft/


https://www.boeing.com/features/2017/11 ... tters.page

[Corsair1963]

Trade off here is the Boeing T-X is a "clean sheet" design. So, it has more risk than an existing design like the T-50. Yet, that risk is modest. While, the Boeing design offers a more custom approach and lower life cycle cost over the life of the program....


Honestly, I personally think it's odds of winning are good....(or at least I hope)