Possible configuration of the Boeing F-47 NGAD

[Scott Kenny]

Friendly bet Scott Kenny regarding the F-47:
Combination of NATF-23 and X-36. Maybe not a full diamond wing but blended into the forward, lifting body fuselage, close-coupled canards, no vertical tails, at least three elevons and possibly thrust vectoring, can't wait to see more actual images at some point.

Deal. Loser buys the first round of beverages!

 

[Scott Kenny]

Yes, same here, though I expect the wing to be more delta than lambda to carry fuel for a Pacific range.

I'm leaning more towards B-21 shape, fuel in the inner portion, but delta is possible (see the Chinese).

 

[FlyGuy369]

And that's when we get this

 

[Low IQ Techie]

Actually, they said it's 46 in (1.1684 m) in diameter:

117cm dia. means 17% more wider & higher than F-22's F119,
1.17^2 almost 37% more inlet area, means more air mass flow
& length also increased by 17% then volume/weight would increase by 1.17^3=1.6 or 60% more.
That's like 17% more XYZ scaled up F-22 for a brief idea.

The expectations seems for the new ones for the F47 to be a bit smaller (as in shorter). Intake size might increase a bit, though.
Very likely. Stealth needs to be compact and reduce surface area which also is the same as wet area, hence, less drag.
My take on the rendered design seems to have the cross section area reduced to ~94/95%.

For VCE, a 3rd channel air flow should increase diameter. If outer channel dia. is restricted, so is inner channels, means impact on thrust.

For flight at differnt speeds & altitudes, the area of intake, engine inlet & exhaust are related mathematically, IDK exactly how. Those propulsive efficiency formulas & equations are too much for me to handle.

How can a 6gen jet have :
- more weapons
- more fuel
- more range
- more speed
BUT engines smaller than previous ones?

If you reduce CS by 4-5%, then volume has to be compensated by increasing length, impacting area required for intakes, inlets, as i showed in diagram few pages back.

 

[Seragina]

Why do you say that?

Complexity naturally increases "failure points".

If we are talking only about radiation mitigation. Then it would come down to skin thickness or shielding thickness if you will. That's why the F22 is heavier than the F15 even though volume wise they are close. You would think thicker is better but it's not that simple.
There's a limit to mass attenuation coeffient (absorbtion) that can be achieved and even then scattering can still result in a lensing effect (buildup). Because of that your calculations always end up with an underestimated rate. That's why real world measurement is always required for verification. And we aren't even going into "streaming" yet.

 

[Kat Tsun]

I fully expect that Boeing's design looks like a cross between the X-36 and Bird of Prey, scaled up to twin engines.

And that LockMart's design looked like the FB-22/X-44.

Ye given McDD and Boeing's history, it has the potential to be either the prettiest or the ugliest plane ever made, there is nothing in between.

 

[Seragina]

For VCE, a 3rd channel air flow should increase diameter. If outer channel dia. is restricted, so is inner channels, means impact on thrust.

Nah, more channel doesn't increase inlet size because the core (combustion chamber) is always much smaller. After all the air is compressed before being burned.

For flight at differnt speeds & altitudes, the area of intake, engine inlet & exhaust are related mathematically, IDK exactly how. Those propulsive efficiency formulas & equations are too much for me to handle.

That's why you should normalize it to sea level. For the F22 I think it was around 250 kg.
The problem here is we don't know if VCE and thrust increase given is normalized or not. This isn't your ordinary engine. The papers seems to give only a 10% increase for this technology. So the other missing 10% might indicate a need to increase air flow, hence, intake area.

How can a 6gen jet have :
- more weapons
- more fuel
- more range
- more speed
BUT engines smaller than previous ones?

If you reduce CS by 4-5%, then volume has to be compensated by increasing length, impacting area required for intakes, inlets, as i showed in diagram few pages back.

Look at my posted schematics. Counting pixels the CS was reduced to about 91.4% right after the intake section.
The saved space is due to the intake ducts no longer present or rather only 33% left for my design idea ofhaving it split up.

The removed fuel volume is compensated by incresing wing area which is required due to increased weight (payload+more fuel: a vicious cycle) and body length (longer IWB).

What I've not mentioned yet are the options for reducing intake duct volume.
Aside from DSI there are three more:
1. A slit design. It's the simpless of all but it seems to require an increase in "incoming" length at the lip. So not ideal for a small craft. I like it best due to simplicity eventhough I'm not certain about all the parameters that make it work yet.
2. A skrew duct. It reduces length dramatically due to the nature of round surfaces being large. Frankly, for the same reason it's undesireably wide and wiggling around. And imho the unused space is wasted and unuseable.
3. A similar design to above but applied to an ordinary duct. My bet is on this design.

I'll post a revised sketch sometime later for an evolved redesign but still losely based on the rendered design/source from the video.

 

[Sferrin]

And that's when we get this

Please. I'm eating lunch.

 

[Training_Dummy]

I thought the benefit of the third stream from adaptive engines was a) higher bypass for cruise efficiency b) power generation c) cooling and for less conventional things like fluidic thrust vectoring or novel control effectors. Given the rumors the first spiral of F-47 won’t have a three stream engine, we probably have to wait some time for the more fully realized version (hopefully not as long as Block 4 F-35!).

 

[bring_it_on]

Given the rumors

What are the sources of those rumors? Do they point to any specifics about what other configurations the first operational F-47's will have?

 

[Training_Dummy]

Point taken about the quality of the rumors and there has been a lot of noise with minimal powerplant info for F-47. That said, someone smarter than me pointed out GE and PW have not even built full XA102 and 103 demonstrators, to say nothing of testing and validation, implying F-47 IOC is a lot father out that the optimists believe or there is an interim powerplant (and what this means for the nozzle and other fluidic schemes like active flow control as integral effectors or not).

From what I have gleaned, and indicated in the post, such reports are a headscratcher for me given how integral VCE are to a lot of the more advanced FATE/ICE/JAST type notional concepts that NGAD presumably draws from.

Also posts like this
Post in thread 'USAF/USN 6th Gen Fighters - F/A-XX, F-X, NGAD, PCA, ASFS News & Analysis'
https://www.secretprojects.co.uk/th...-ngad-pca-asfs-news-analysis.3536/post-599055 keep me guessing to be honest.

 

[Scott Kenny]

Ye given McDD and Boeing's history, it has the potential to be either the prettiest or the ugliest plane ever made, there is nothing in between.

I cannot find any faults in this logic.

I'm hoping X-36+BoP, because at least that's attractive to me.