Say Hello to the RQ-180

gariac

My point is this: if you know something, just post it or keep your mouth shut. There really is no middle ground here. That is the way I roll.

How I 'roll'? I tell people with your attitude to go # themselves. Then I point out that the internet is for every one not just folks like you on your bull# high horse. When this is your server, your web oage, take the moral.high ground and get all lordy.

Until then, have a nice.cup of shut the hell up.

gariac
A bomber isn't a long endurance aircraft, so it would not have wings as large as the RQ-180.

It's not? Then how do they fly global strike missions?

Zaphod58

gariac
A bomber isn't a long endurance aircraft, so it would not have wings as large as the RQ-180.

It's not? Then how do they fly global strike missions?

B2b wings are long. Its range is obscene. It refuels in the air. Just looking at its nonstop combat missions makes me think 'dear Lords the range on that global reach bomber is obscene.

Zaphod58

gariac
A bomber isn't a long endurance aircraft, so it would not have wings as large as the RQ-180.

It's not? Then how do they fly global strike missions?

They B-2 can use a tanker. I do see your point though. Maybe I should say a long loiter time for ISR type aircraft like the current class of UAVs.

You have to wonder a bit about the RQ-170. [Note 170, not 180] It doesn't have that great of a wingspan, so it probably can't loiter as say a Predator or Reaper. That means it probably has a different mission that a Predator/Reaper. You'll note some of these newer UAS are jet powered to reduce the time to get to the target.

Now probably the RQ-170 is used for known targets, while a Predator/Reaper is used to find targets. Obviously I have no first hand knowledge of this, but you can surmise such things based on the capabilities of the aircraft.

If you read the biography of John Boyd, you get some insight into the design of the aircraft back in the "Fighter Mafia" days. Damn interesting stuff, especially the philosophy behind the A-10. Pierre Sprey, part of the Fighter Mafia, is still kicking. He is probably the biggest opponent of the F-35, since his philosophy is one airplane can't do every task well.

How would you like this title on a business card: aircraft designer, defense analyst, and record producer.
Pierre Sprey wiki

The Fighter Mafia was good. F-15, F-16, A-10. Who can argue with that? [Actually, they just tolerated the F-15, with the F-16 being the preferred fighter.] I really wish some author of aviation books would corner Sprey for a biography before he or perhaps his mind leaves us.

gariac

SirDrinksalot

darksidius


So what is your thinking, a Stealth Nuclear Bomber...yeah, after closing the cold war, the west want an invisible first strike weapon..and if they do...I will join the other side.

Bone up on your Russian, comrade. The US already has two or three stealth cruise missiles. As what is the B-2 other than a stealth nuclear capable bomber?

A bomber isn't a long endurance aircraft, so it would not have wings as large as the RQ-180.

Apologies to SirDrinks a lot. I'm not sure how I did that, but it makes it look my writing was his.

gariac

Bone up on your Russian, comrade. The US already has two or three stealth cruise missiles. As what is the B-2 other than a stealth nuclear capable bomber?

A bomber isn't a long endurance aircraft, so it would not have wings as large as the RQ-180.

Pass me the Vodka comrade, I am not sure what I was talking about!

But....perhaps the longer loiter capability means that you dont have to take off with a set target, but you can loiter with intent..

I agree with him ^

Didnt realise I had two accounts!!

reply to post by IamSirDrinksalot


A good book with a poorly chosen title is "Predator" by Matt Martin. He was stationed at Creech, and also flew UAVs in the sandbox. The book goes into the routine or a UAV driver. Much of it was just patrol. They would fly to an area of known troublemakers, hang out as long as possible, then return to base. So the mission called for excellent fuel economy, hence a long wing, i.e. a high glide ratio. With the mission somewhat nebulous, they would fly with two types of warheads in the Hellfire missiles, depending on who or what they wanted to terminate with extreme prejudice.

For a bomber, the target is usually already known. [For the F117, there was little wiggle room on what was the target.] If you listen to a full session of Red Flag, you can get a good idea how a war is run. It usually starts with a Wild Weasel task, i.e. find the air defenses and eliminate them. Fighter aircraft have stubby wings, so they can maneuver adeptly. Good for dodging rockets and other aircraft that don't like you. The bombers come into play later when the air defenses have been terminated. The larger wings of the bomber make it hard to maneuver. If you watch the B-2 in a airshow, it doesn't do a hell of a lot other than fly by. At Edwards, they will do a loop. Every other show I've been to just has a B-2 pass. I assume if you can do a loop, you can do a Cuban 8, but who wants to risk a 2 billion dollar aircraft flying stunts.

So the bomber doesn't loiter. It just flies to the target, drops the bombs, and returns to base. The F-117, which most people point out is not a fighter but actually a bomber, is an interesting compromise. It doesn't carry much in the way of bombs compared to a B-52 or B-1B. Then again, it doesn't need fighter type aircraft to remove the threats before it enters denied territory. So you wonder why they canned it. You would have to do an analysis to compare the weapons bay of the F-22 and F-35 compared to the F-117. Since the F-22 and F-35 are stealthy, if they can carry the same amount of weapons, then you wouldn't need the F-117.

reply to post by gariac


The trouble with aircraft design of a spanloader (flying wing) is you have a limited max trimmed overall lift coefficient (not just airfoil, but 3D wing). This is because of no pitch trimming mechanism, such as a horizontal stabilizer or canard. This wreaks havoc with your max trimmed L/D (glide ratio) across a range of dynamic pressures. You generally build a wing for two parts of a mission - launch/recovery and either ingress/egress or loiter. You can get an excellent max trimmed L/D on a flying wing, but it's usually at the ingress/egress speed, since loiter generally requires you to fly slow (i.e. dynamic pressure). Flying wings don't like slow (L = qbar * Sref * CL => CL = 0.6 so Sref needs to be large at a given qbar (dynamic pressure).

With this in mind, I've run synthesis models on aircraft, including RQ-3A, and you find the "legs" on the flying wings are small when you look at a loiter mission. So, this is consistent with Bill Sweetman's 5-6 hr estimate on the RQ-170 time aloft. IMHO, this considered - the RQ-180 has sprouted a tail for trimming pitch at loiter, and to counter the yawing-rolling (lateral-directional) moments you get off large aspect ratio wings from aileron deflection. This is why sailplanes have large vertical stabilizers. One could argue there are split slot deflectors on the upper outboard surface, as depicted in the Av Week art, however, I would ask whether the drag penalty of such is worth it in lost endurance. Nothing wrong with a v-tail/dual inward canted tail from a broadband low observable perspective, as shown in the F-117/HAVE BLUE configurations. I have cut a portion of a Northrop image that Astr0 posted earlier in this thread below, depicting what I believe is a reasonable layout of the RQ-180.

Image: Possible RQ-180 Configuration Design

You may notice a lack of wing sweep to redirect incoming EM energy from threat emitters, but bear in mind the name of the game is location of the threat w.r.t. your body - assuming a monostatic radar. Look at ACM-129, the greatest threat is from the top side (think JSTARS), so you place your vertical and inlet on the opposite side (underneath). The RQ-3A, greatest threat is from the side. F-117, greatest threat is from head on, so you add sweep and a serpentine inlet or inlet grid and so forth.

"The four most important aspects of stealth are shape, shape, shape and materials." - Denys Overholser

reply to post by TAGBOARD


Wouldn't the problem with the aircraft in your picture, is that the V-tail would have an extremely small movement arm? I would have thought a split trailing edge like B-2 and X-47 would be more likely. Thoughts?

What surprise,, me it's the announcement of the RQ-180 soon after the SR-72, its a little the same mission in the ISR domain. Is it a war between two concept ? one is the speed and the other just with the stealth. For my opinion survive in a high hostile theater just with the stealth for defense is very dangerous , I hope USAF don't put all the eggs in the same bag.

reply to post by TAGBOARD


One problem with maneuvering UAVs is maintaining the satellite link. Looking at UAV shapes, some have a rounded shape at the front and others look sleek and stealthy.

The rounded shape is due to a dish antenna. Basically it needs room to rotate. Predator/Reaper flight maneuvers are limited by the slew of the satellite dish.

But clearly we have had UCAV capability for some time. Unless anyone knows what change took place to get around the dish problem, when doing open source searches on UAV tech, keep an eye out for changes in comm tech.

All that said, you don't need a lot of agility for ISR. That is probably part of the design parameters.

darksidius
What surprise,, me it's the announcement of the RQ-180 soon after the SR-72, its a little the same mission in the ISR domain. Is it a war between two concept ? one is the speed and the other just with the stealth. For my opinion survive in a high hostile theater just with the stealth for defense is very dangerous , I hope USAF don't put all the eggs in the same bag.

Given the problems NASA has had with hypersonic flight, I don't put touch faith in the SR-72. I don't even think they would use the SR designation given the history of SR versus RS.

If the SR-72 speed is to get to the target, you have to wonder where the US lacks a base nearby.

gariac

Zaphod58

gariac
A bomber isn't a long endurance aircraft, so it would not have wings as large as the RQ-180.

It's not? Then how do they fly global strike missions?

You have to wonder a bit about the RQ-170. [Note 170, not 180] It doesn't have that great of a wingspan, so it probably can't loiter as say a Predator or Reaper. That means it probably has a different mission that a Predator/Reaper.

RQ-170 only has a bout four or five hours on station (depending on distance to loiter area). That's why it appeared pretty close to the lines on the map denoting Pakistan, Iran, Korea, China ,etc.

gariac
If the SR-72 speed is to get to the target, you have to wonder where the US lacks a base nearby.

Pacific Pivot.

There are some goodly distances involved, which could turn a high-speed aircraft into an asset. You can place the base of operations far enough away from a threat to be "safe" and still maintain an effective reaction time.

I could fly a U-2/RQ-170/etc out of Osan, but think of how much safer it would be to fly a hypothetical SR-72 from Guam, have the same flight times, add the complexity of speed/time to the defenses in question (N.Korea, for example), and leave your base of operations much more secure. Sure, someone could escalate and lob an IRBM or something at Guam, but that's a lot less likely than a scenario involving a small horde of Koreans crossing the DMZ (either covertly, "sabotage" or en masse to overtake or destroy key areas like Osan. A handful of people with a 120mm mortar or two will effectively shut down an airfield for a decent amount of time. By the time the event has expired perhaps what you really needed to monitor is over and done).

reply to post by _Del_


Or to be even a little safer, base it in Misawa, or Kunsan.

If the balloon went up, I'd rather have the assets in Guam. You have to have permission from Japan to operate out of Misawa or Kadena, which you may or may not get depending on the situation. And while basing from the southern tip of the peninsula would be fine for something with short legs, Guam's location is pretty ideal for going anywhere in the theatre. It's a lot harder to hassle Guam as well. In any event, a hypothetical SR-72 (and the RQ-180, I'm sure, as well) is a compliment to existing, conventional ISR platforms. The main advantage is the ability to penetrate denied airspace where you couldn't get an Avenger or Global Hawk, etc. Neither is going to be produced in numbers to replace those sorts of platforms.

reply to post by _Del_


Oh, Guam is by far the better option, since it's US territory. I was just throwing out other options as well.

Northrop have been using flat panel AESA for testing aircraft to satellite high speed high bandwith communications.

Our demo marks the first time that AESA antenna technology has been used to communicate with the AEHF network," said Byron Chong, Northrop Grumman's B-2 deputy program manager. "We showed that our antenna will consistently produce and maintain the high-gain beam needed to communicate with AEHF satellites."

It would not surprise me in the slightest if dish antenna are now a thing of the past and flat panel units shaped for their required mission profile are now inside the VVLO offerings.

Astr0
Northrop have been using flat panel AESA for testing aircraft to satellite high speed high bandwith communications.

That's already been in use for SATCOM for some UAV's, but it hasn't really been advertised. The tech has actually been around since the 90's. The first NG is talking about there is for the B-2 AESA specifically, which adds a capability. It isn't even really NG's first foray into the underlying technology.