US Navy’s UCLASS / CBARS / MQ-XX / MQ-25 Stingray Program

[Mat Parry]

And when the Navy go "OH NO!!! WE NEED LOW OBSERVABLE STRIKE! !! HELP!!" NG can just drop the gas tanks and laugh as they trolled the Navy hard.

The X-47b is not stealthy even after dropping hose refuelling pods. It is simply a demonstrator that is representative of a stealthy shape. If NG won the contract and applied the low observable treatments, antennae etc. when the requirements did not dictate it, then their profit margins would be reduced considerably.

 

[sferrin]

And when the Navy go "OH NO!!! WE NEED LOW OBSERVABLE STRIKE! !! HELP!!" NG can just drop the gas tanks and laugh as they trolled the Navy hard.

The X-47b is not stealthy even after dropping hose refuelling pods. It is simply a demonstrator that is representative of a stealthy shape. If NG won the contract and applied the low observable treatments, antennae etc. when the requirements did not dictate it, then their profit margins would be reduced considerably.

And it would still be cheaper than starting over with a completely new design, and get to the fleet sooner.

 

[Mat Parry]

And it would still be cheaper than starting over with a completely new design, and get to the fleet sooner.

Agree, I'm a huge fan of what Northrop achieved with the X-47b but let's not pretend a tanker version will also be low observable platform under the Navy's current requirements

 

[Ian33]

And it would still be cheaper than starting over with a completely new design, and get to the fleet sooner.

Agree, I'm a huge fan of what Northrop achieved with the X-47b but let's not pretend a tanker version will also be low observable platform under the Navy's current requirements

So the shape, engine, all the same? Just systems and skins updated for the later strike models. Sounds like a perfectly reasonable development path. Like a F35 of the drone world.

 

[Mat Parry]

So the shape, engine, all the same? Just systems and skins updated for the later strike models. Sounds like a perfectly reasonable development path. Like a F35 of the drone world.

Adopting a platform that is designed with a development path towards increased levels of low observable characteristics is an eminently sensible idea if it can be done cost effectively (if that happens remains to be seen). So in the short term "just drop the gas tanks"... Erm no.

I actually think we're generally in agreement here and we've wasted enough electrons on this debate.

 

[TomcatViP]

Still, I am a little bit surprised that Northrop didn't include any added ctrl surface to mitigate the frustrated expectation expressed by the Navy when they stated that the wing body design was more suited for a carrier aircraft. Unless they have a trump card, obviously.

 

[bring_it_on]

There is no guarantee that Northrop's final submission looks exactly like the X-47B prototypes. They may be using the prototypes they have to de-risk certain areas of their proposal.

 

[sferrin]

Still, I am a little bit surprised that Northrop didn't include any added ctrl surface to mitigate the frustrated expectation expressed by the Navy when they stated that the wing body design was more suited for a carrier aircraft. Unless they have a trump card, obviously.

The Skyray didn't seem to have any problems, and was one of the better naval aircraft of its time. Sounds more like the USN getting twitchy over the unfamiliar. (And yes, yes, safety comes first when it comes to carrier aircraft, but if the USN never got out of its comfort zone they'd still be flying tail-draggers.)

 

[TomcatViP]

The Skyray had a vertical tail... with a rudder. Much less draggy than two massive split flaps during a carrier landing.

 

[sferrin]

And the X-47 has much more power, lower wing-loading, and computer control. I'd also argue that the X-47 has lower drag (for its size) to start with anyway. Looks like it's flying at a lower AOA too. I don't think having "too much drag" is a factor.

 

[marauder2048]

The Navy looked at belly flaps and a retractable canard. Of course blown flaps or other
lift augmentation techniques are a Navy no-no despite the fact that variable cycle
engines excel at such things...

 

[Airplane]

And when the Navy go "OH NO!!! WE NEED LOW OBSERVABLE STRIKE! !! HELP!!" NG can just drop the gas tanks and laugh as they trolled the Navy hard.

The X-47b is not stealthy even after dropping hose refuelling pods. It is simply a demonstrator that is representative of a stealthy shape. If NG won the contract and applied the low observable treatments, antennae etc. when the requirements did not dictate it, then their profit margins would be reduced considerably.

And it would still be cheaper than starting over with a completely new design, and get to the fleet sooner.

x2

 

[sferrin]

The Navy looked at belly flaps and a retractable canard. Of course blown flaps or other
lift augmentation techniques are a Navy no-no despite the fact that variable cycle
engines excel at such things...

The USN has had many planes with blown flaps. ???

 

[_Del_]

There is no guarantee that Northrop's final submission looks exactly like the X-47B prototypes. They may be using the prototypes they have to de-risk certain areas of their proposal.

That's exactly what is going on. "Look we can do this. We've been there. The underlying technologies are mature."
The actual proposal is almost sure to be larger than X-47B to get any sort of useful offload at distance.

 

[sferrin]

There is no guarantee that Northrop's final submission looks exactly like the X-47B prototypes. They may be using the prototypes they have to de-risk certain areas of their proposal.

That's exactly what is going on. "Look we can do this. We've been there. The underlying technologies are mature."
The actual proposal is almost sure to be larger than X-47B to get any sort of useful offload at distance.

If it were significantly larger they'd have to go to something like a non-afterburning F135. (As I recall, the most powerful F100/F110 variant only put out about 21-23k dry.)

 

[litzj]

my opinion, NG propose enlarged x-47 as final form of mq-25 to make better end product

x-47 had technical demonstration purpose which showed aerial refuel, weapon delivery, take off and landing

they are major hurdle of carrier-used-unmanned aircraft.


finalized NG product will show low observable form with modular design

which can change its mission module as dew weapon, missile, bomb carrier, refueling, even as electronic, surveilence...


this is just my opinion.

 

[Flyaway]

Modified X-47B Breaks Cover As Testbed For MQ-25 Bid

LOS ANGELES—Northrop Grumman is using an X-47B unmanned air vehicle (UAV) as a flying testbed for air refueling systems in support of its proposal for the U.S. Navy’s upcoming MQ-25A Stingray unmanned aerial refueling tanker contest. First details of Northrop Grumman’s preparations for the MQ-25A bid have emerged in photographs obtained by Aviation Week of a modified X-47B at the U.S. Air Force’s Plant 42 facility in Palmdale, Calif. The photos appear to show the UAV ...

http://m.aviationweek.com/defense/modified-x-47b-breaks-cover-testbed-mq-25-bid

 

[_Del_]

If it were significantly larger they'd have to go to something like a non-afterburning F135. (As I recall, the most powerful F100/F110 variant only put out about 21-23k dry.)

X-47B can't offload anything meaningful at a distance. The proposal is going to be bigger. Last known pitch was twin TF34, and a much larger span.

 

[sferrin]

If it were significantly larger they'd have to go to something like a non-afterburning F135. (As I recall, the most powerful F100/F110 variant only put out about 21-23k dry.)

X-47B can't offload anything meaningful at a distance. The proposal is going to be bigger. Last known pitch was twin TF34, and a much larger span.

Twin TF34 X-47? A shape like that big enough to stuff two TF34s inside seems like it would be underpowered. ???

 

[_Del_]

A-6 made do with roughly the same thrust as twin TF34s with worse fuel consumption and a hefty bombload. A-7 had even less thrust, but they both had legs and the ability to haul weight. If you want range, tankage, and persistence, twin TF34s are probably the way to go. TF-34 arrangement only needs three inches more depth than a single F118, and the SFC is much greater while providing the same thrust. The engine is also cheap and incredibly reliable. You are already making a wide aircraft with a deep body. You want to carry more than the 5000 or so lbs of fuel available for offload in an X-47B any sort of diatance, it's going to need to be a bigger aircraft.

 

[marauder2048]

The Navy looked at belly flaps and a retractable canard. Of course blown flaps or other
lift augmentation techniques are a Navy no-no despite the fact that variable cycle
engines excel at such things...

The USN has had many planes with blown flaps. ???

I think *had* is the operative word here. The perception amongst most offerors is that the Navy (because of the long institutional memory of
the maintenance intensive nature of the F-4's blown flaps implementation) does not favor lift augmentation.

Last known pitch was twin TF34, and a much larger span.

Might as well bring back the S-3 in unmanned form.

 

[sferrin]

A-6 made do with roughly the same thrust as twin TF34s with worse fuel consumption and a hefty bombload. A-7 had even less thrust, but they both had legs and the ability to haul weight.

TF-34 dia: 49" - 57" depending on model
J52 dia: 38"

TF-34 arrangement only needs three inches more depth than a single F118, and the SFC is much greater while providing the same thrust.

F118 dia: 46"

The TF-34 solution might only be three inches more in depth but it's over twice as wide. The thing would be so different than an X-47 in configuration it would cease to be one and be a completely new design. Cha-ching.

 

[_Del_]

It's going to be a new design. Beyond the general planform, the offering isn't going to be much more like the X-47B than the B was like the A. The new requirements might put even the planform up for grabs because the focus on mission tanking and relaxing RCS requirements is a step away from VLO strike/recce (and a tail might be helpful in a larger, heavier aircraft).
The B is a technology demonstrator just like the A. Noone is talking about shoehorning two TF34s in something the size of a B. The B doesn't have the payload capacity to lug "robust fuel offload at range".
Is twice as wide really a concern for a 70+ span lifting body? Probably not.

 

[sferrin]

It's going to be a new design. Beyond the general planform, the offering isn't going to be much more like the X-47B than the B was like the A.

I'd bet money it's going to be more like Hornet / Super Hornet than X-47A/B The only thing in common on the latter two was the "X-47" part of their name.

 

[_Del_]

So the same general planform and internal systems, but larger, more powerful, and sharing little or no actual commonality of airframe? That's what I just said...

 

[NeilChapman]

Still, I am a little bit surprised that Northrop didn't include any added ctrl surface to mitigate the frustrated expectation expressed by the Navy when they stated that the wing body design was more suited for a carrier aircraft. Unless they have a trump card, obviously.

The Skyray didn't seem to have any problems, and was one of the better naval aircraft of its time. Sounds more like the USN getting twitchy over the unfamiliar. (And yes, yes, safety comes first when it comes to carrier aircraft, but if the USN never got out of its comfort zone they'd still be flying tail-draggers.)

Agree completely.

NG has to make this an obvious choice. Any maintenance commonality to the F-35C, e.g leveraging tech expertise would go a long way.

F-35 items produced by NG to consider including or offer as options for MQ-25...

Internal navigation - Include
GPS System - Include
Landing aid antennas - Include
Common Components - Include
Racks
Power Supplies
Module Kits
Network Interface Units used in dev of all avionics subsystems
CNI - Include
UHF/VHF Voice/Data
IFF
Link16
Inflight Door drive systems - Include

MADL - Optional (Show ability to integrate)
Multifunction Advanced
Data Link
AN/AAQ-37 DAS - Optional (Show ability to integrate)
AN/APG-81 AESA - Optional (Show ability to integrate)

Lastly, perhaps they need to change the engine. It needs to be something already in use on the carriers or on its way. The Super Hornet's F100 or the F135. With the F135 at least it would be "ready" for the future AETP engine.

 

[sferrin]

So the same general planform and internal systems, but larger, more powerful, and sharing little or no actual commonality of airframe? That's what I just said...

No, you said a twin-engine vehicle. "Last known pitch was twin TF34, and a much larger span."

 

[sferrin]

The Super Hornet's F100 or the F135. With the F135 at least it would be "ready" for the future AETP engine.

Probably a brain-fart but the Super Hornet uses the F414, which in a non-afterburning configuration would be too small. However, the USN does have experience with the F110 in the F-14D, and the F118 (used in the B-2) is a non-afterburning version of that engine.

 

[flateric]

...

 

[Airplane]

...

How many gallons does she carry? Would it make sense to design a LO fuel tank for refueling closer to the strike zone?

 

[sferrin]

...

How many gallons does she carry? Would it make sense to design a LO fuel tank for refueling closer to the strike zone?

Even the F-22 doesn't use a LO external tank.

 

[TomcatViP]

There was a vid on the net with the exact fuel contenance. Posted it somewhere else. Have to find it back.

 

[bring_it_on]

The X-47B was advertised as having >3500 nm of range at maximum payload so it probably carries a fair bit of fuel.

 

[Airplane]

...

How many gallons does she carry? Would it make sense to design a LO fuel tank for refueling closer to the strike zone?

Even the F-22 doesn't use a LO external tank.

Doesn't mean it isn't possible. Only that it was not a requirement or there was no funds. The -35B/C uses a LO gun pod.

 

[sferrin]

...

How many gallons does she carry? Would it make sense to design a LO fuel tank for refueling closer to the strike zone?

Even the F-22 doesn't use a LO external tank.

Doesn't mean it isn't possible. Only that it was not a requirement or there was no funds. The -35B/C uses a LO gun pod.

Because punching off a gun pod wouldn't be anybody's first choice.

 

[TomcatViP]

The X-47B was advertised as having >3500 nm of range at maximum payload so it probably carries a fair bit of fuel.

+Aerial Refueling has ever been part of the planned mission (USN & USAF)

 

[Airplane]

...

How many gallons does she carry? Would it make sense to design a LO fuel tank for refueling closer to the strike zone?

Even the F-22 doesn't use a LO external tank.

Doesn't mean it isn't possible. Only that it was not a requirement or there was no funds. The -35B/C uses a LO gun pod.

Because punching off a gun pod wouldn't be anybody's first choice.

No, no no.... Just an example of LO equipment hanging from the bird. LO external tanks ought to be very easy to develop. Sure it won't be a free lunch, and would increase RCS especially from the side, but when keeping its distance you could have a stealthy tanker for the USN.

But I like someone else noted, don't believe the unmanned tanker won't be a stealthy aircraft. Too bad, because the tech is there, and there is always a need for tanking up for the foreseeable future.

 

[litzj]

LO design requires expensive material and special OML design for the specific applied vehicle;

Modifying internal bay for aerial refueling is more reasonable to maintain LO performance

 

[_Del_]

The use of the existing buddy pods is part of the requirement.

So is the ability of offload a lot of fuel. Unlikely to be X-47B sized with a gross weight of 44,000lbs.

 

[Sundog]

I seriously doubt this is the vehicle they're offering. What they're doing is flying a proof of concept to back up whatever their proposal is going to be and to give their engineers more data on unmanned aerial refueling with manned and possibly other unmanned aircraft. I don't see the X-47B meeting the cost goals, as stealth adds a lot of cost, in terms of both procurement and maintenance. Few airframe manufacturers have ever won a competition by offering a vehicle that exceeds the cost/performance goals of the contract.