Looking past/through propeller blades isn't that big a problem. E-2 has a similar thing and it's just never been a major issue.

There are at least two configurations shown for V-22 AEW aircraft. One has a dorsal radome -- either a traditional disk or a fixed triangular housing, depending on the timeframe.

DQk2pmgX4AIoTxq.jpg


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The other is basically the existing Cerberus AEW radar on a pallet that lowers the radome out the rear ramp. The USMC was interested in the latter (as TOSS) for tracking both air and surface targets, but nothing came of it.


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The belly-mounted radar reminds us of the long-range radar retrofitted to (British) Royal Navy Sea King helicopters during the Falklands War in 1982.
A similar extendable radar was later fitted to a few RN EH101 Merlins for the naval AEW role.
 
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if one were to design an AEW on a tilt rotor, wouldn't the Osprey be a better choice than the Valor due to it being bigger?
They will use nearly the same engines, and Osprey has more drag, so going with V-22 means taking a range/loiter time hit in exchange for more internal volume. In a traditional AEW that's a good trade since you want the volume for mission operators and cooling for the payload. But we could be a the point where we see someone try leaving everyone but the pilots on the ground, which would shrink the needed internal volume considerably.
 
@TomS : the radar use a rotating antenna protected by an inflated cupola.
There is no need for rotation given the budget that will be allocated to such strategic platform and no need for an inflated envelope with a conformal mounting not interacting with the landing gear.

See also how the lower loitering speed will tilt the attitude up, exposing the front sector to the radar.

I look at those solutions as being dated and not relevant for the application we are discussing here.
 
@TomS : the radar use a rotating antenna protected by an inflated cupola.
There is no need for rotation given the budget that will be allocated to such strategic platform and no need for an inflated envelope with a conformal mounting not interacting with the landing gear.

See also how the lower loitering speed will tilt the attitude up, exposing the front sector to the radar.

I look at those solutions as being dated and not relevant for the application we are discussing here.

I still don't see how a radar antenna flush or slightly bulged outward from the rear ramp can look forward, unless the plane is flying severely nose-up. Which isn't likely. I mean, Osprey pitches up 3-5 degrees at refueling speeds (~210 knots), surely not much different than max-endurance speed.

Would you propose a separate array in the nose to cover the front sector? I'm just not visualizing this well. Perhaps a sketch?

The assumption that AEW solutions (tilt-rotor or otherwise) will not be sharply budget-constrained is not what we've seen so far. CROWSNEST was severely budget-constrained, which is why they adopted this rather basic solution. A near-future British Armyt or USMC program is also likely to be very constrained budget-wise. That's a big part of why Cerberus/TOSS looked attractive, compared to the dedicated EV-22 with a radome on top.
 
Unless the stealth materials are able to tolerate mud and uncontrolled atmospherics (temp and humidity) along with tired dirty maintainers working on them, it will not buy its way onto the basic Army platform. The revelation that the RAH-66 Comanche would have to operate from prepared surfaces was one of the final "nails in the coffin" for that program. Army lives and fights in fields, especially now that airfields are whacking great targets that even the USAF are concerned about.
And whats the V22?

Those apperantly have blades thats bout 60 radar transparent. And are know to bum around in the desert without any issue.

Throw in the fact the B21 and F35 is noted to not need temperature control hangers? With Marines F35 notably chilling outside on LHA decks thru ocean storms?

Eyeah dont believes that is much of a problem any more like it was oh...

18 years ago with the RAH66.
 
I'm pretty sure that looking through the rotor disk is not conducive to high radar performance.

How about Erieye on one side of the fuselage with a trapeze to lower it in flight? Can see both sides and should be below the rotors in max endurance configuration.
 
@TomS : I will sadly have no time to sketch that down. But reading your value and looking at refueling video, don't they use a notch of flap?

In any case,
1. Negative flap (slightly) can help adding AoA for a more compliant nose up attitude (and certainly not impact much the overall drag)
2. The "bulge" housing the conformal radar can be made actuated, protruding more in flight and raised when not in use. Let's not forget that we are discussing here a reworked rear ramp door that could use the built-in actuation.

Edit:
@red admiral beat me to it.
 
@TomS : I will sadly have no time to sketch that down. But reading your value and looking at refueling video, don't they use a notch of flap?

In any case,
1. Negative flap (slightly) can help adding AoA for a more compliant nose up attitude (and certainly not impact much the overall drag)
2. The "bulge" housing the conformal radar can be made actuated, protruding more in flight and raised when not in use. Let's not forget that we are discussing here a reworked rear ramp door that could use the built-in actuation.

Edit:
@red admiral beat me to it.

I think I'm getting it. It's an articulating antenna housing that sticks out below the fuselage? Not fundamentally different, IMO. Just a question of how much money people are willing to spend. And so far, the answer to that seems to be "not much"
 
A near-future British Armyt or USMC program is also likely to be very constrained budget-wise. That's a big part of why Cerberus/TOSS looked attractive, compared to the dedicated EV-22 with a radome on top.
Japan, Italy, Spain, UK, USMC, potentially South Korea and Australia, heck even India, there are lots of Navies with an AEW need that can't handle an E-2 but could handle an AEW V-280 or V-22. It might only be a handful of aircraft each, but once you add them all up it might be worth spending the money. Capability wise I think it's a necessity. All of those STOVL carriers would be much, much more useful with organic AEW.
 
wouldn't a "balance beam" style Radar be more appropriate for these tilt rotors than a dish?
 
Unless the stealth materials are able to tolerate mud and uncontrolled atmospherics (temp and humidity) along with tired dirty maintainers working on them, it will not buy its way onto the basic Army platform. The revelation that the RAH-66 Comanche would have to operate from prepared surfaces was one of the final "nails in the coffin" for that program. Army lives and fights in fields, especially now that airfields are whacking great targets that even the USAF are concerned about.
And whats the V22?

Those apperantly have blades thats bout 60 radar transparent. And are know to bum around in the desert without any issue.

Throw in the fact the B21 and F35 is noted to not need temperature control hangers? With Marines F35 notably chilling outside on LHA decks thru ocean storms?

Eyeah dont believes that is much of a problem any more like it was oh...

18 years ago with the RAH66.
Well, here is too hoping you are correct.
 
@TomS : the radar use a rotating antenna protected by an inflated cupola.
There is no need for rotation given the budget that will be allocated to such strategic platform and no need for an inflated envelope with a conformal mounting not interacting with the landing gear.

See also how the lower loitering speed will tilt the attitude up, exposing the front sector to the radar.

I look at those solutions as being dated and not relevant for the application we are discussing here.

I still don't see how a radar antenna flush or slightly bulged outward from the rear ramp can look forward, unless the plane is flying severely nose-up. Which isn't likely. I mean, Osprey pitches up 3-5 degrees at refueling speeds (~210 knots), surely not much different than max-endurance speed.

Would you propose a separate array in the nose to cover the front sector? I'm just not visualizing this well. Perhaps a sketch?

The assumption that AEW solutions (tilt-rotor or otherwise) will not be sharply budget-constrained is not what we've seen so far. CROWSNEST was severely budget-constrained, which is why they adopted this rather basic solution. A near-future British Armyt or USMC program is also likely to be very constrained budget-wise. That's a big part of why Cerberus/TOSS looked attractive, compared to the dedicated EV-22 with a radome on top.
I would have it swing down like the two examples in the Marconi advert Tom. The position I have it in the photos, shows it in the stowed position.
 
I would have it swing down like the two examples in the Marconi advert Tom. The position I have it in the photos, shows it in the stowed position

Got it. Not radically different from the Cerberus config, really. Just a bigger radar body.

Tomcat was talking about something else that took a while to visualize.
 
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Northrop Grumman Flies Candidates For V-280, FARA Mission Systems / Aviation Week
DATE: December 19, 2022

BYLINE: Steve Trimble

Northrop Grumman has tested systems for targeting, communications and navigation in a flying UH-60 Black Hawk, demonstrating mission system candidates in flight for the U.S. Army’s Future Vertical Lift rotorcraft.
The Re-scalable Aperture for Precision Targeting Radar (RAPTR) and Mini-Communications, Navigation and Identification (Mini-CNI) systems are Northrop’s proposals for a common mission system suite needed for the Future Long Range Assault Aircraft (FLRAA) and Future Attack Reconnaissance Aircraft (FARA) programs.
The Army awarded the FLRAA development contract on Dec. 5 to the Bell V-280 Valor tiltrotor. Bell’s 360 Invictus and Sikorsky’s Raider X are competing for the FARA development contract.
The V-280 fleet is expected to operate with weapons in conventional Army units, unlike the non-special operations version of the Black Hawk fleet it replaces. The Army wants to develop a common mission system for targeting and CNI functions between the V-280 and FARA fleets. Due to weight and power constraints, the Army needs multifunctional systems, rather than federated processors and apertures for each subsystem.
“This flight test was a key step in demonstrating the ability to integrate multifunction sensors and advanced communications and networking systems into the FVL ecosystem,” said Susan Bruce, Northrop’s vice president of advanced mission capabilities.
The Army plans to complete a preliminary design for the common mission systems in fiscal 2023, with lab testing following a year later and flight testing beginning in fiscal 2025. In addition to common hardware, the Army also wants a single software baseline and shared applications between the V-280 and FARA fleets.
 
Now then... Here are side views of Valor and Defiant. I had trouble finding a rotor diameter for the Defiant, but 50ft seems to be the concensus, while 35ft seems to be the diameter of the Valor.

Not much difference unless these dimensions are balleaux.

Chris
Defiant: diameter 56.6 ft, length (nose to end of prop spinner) 55.4 ft
Valor: radius 17.58 ft, length OA 50.58 ft
 
Now then... Here are side views of Valor and Defiant. I had trouble finding a rotor diameter for the Defiant, but 50ft seems to be the concensus, while 35ft seems to be the diameter of the Valor.

Not much difference unless these dimensions are balleaux.

Chris
Defiant: diameter 56.6 ft, length (nose to end of prop spinner) 55.4 ft
Valor: radius 17.58 ft, length OA 50.58 ft
Thanks OBB, just what I need. oddly enough today has seen quite a few V280-related Christmas presents.

Chris
 
Back to having a AEW variant of the Valor, I would have thought that having 2 repositional AESA radars in nose and tail mounted radomes would do the trick.

l also wonder if the fuselage could be stretched airliner style for non-tactical assault missions or be fitted with a rear ramp for the naval COD role. Having the fuselage free of the propulsion system seems like an advantage over the highly integrated Defiant layout.

Chris, fancy doing a mashup of a Valor wing on a P.139C-1? :)
 
It was inevitable of course. too much money involved. The Army was fully expecting this and even mentioned it as part of the plan, at the news conference announcing the winner. Here is to this does not take 100 days.
 
Yeah, its almost as though these days Defense contracts have an additional round: Determine requirements - RFI/RFP/RFT - Responses submitted - Evaluation - Announcement of winner - Deal with Legal Challenges - Negotiate - Enter Contract. Sigh.... :rolleyes:

I also wonder if people doing such things take the time to consider how such will play out for future relationships even if they are successful. After all, one will have to work with the team that you just publicly told made the wrong decision...
 
Sigh...I get tired of these sorts of things:

The challenge process is there for a reason. Sometimes favoritism is indeed involved--probably more often than we think, given the revolving door between the military services and the vendors. Protests, reviews, and litigation are just what it costs to keep military procurement somewhat honest.
 
Sigh...I get tired of these sorts of things:

The challenge process is there for a reason. Sometimes favoritism is indeed involved--probably more often than we think, given the revolving door between the military services and the vendors. Protests, reviews, and litigation are just what it costs to keep military procurement somewhat honest.
To quote a poster on another board

The actual number of protests received by GAO and the CoFC is significantly less than during the Cold War, under a thousand cases annually. The majority of which are from small businesses concerning contracts measured in millions, not billions, of dollars, and frequently less than that. Even then, only 0.3% of contracts issued by DoD are protested to GAO, and of those only 12% see corrective action; in fact only 3% of protests received by GAO are actually sustained, the other 9% received corrective action prior to a GAO reccomendation.
The government doesn't always do themselves any favors here either when they can be unnecessarily opaque and adversarial in post-award debriefings. Contractors that don't feel they are getting the whole story out of the government tend to protest, and better debriefing policies instituted by the Army and Air Force have correlated to reduced volumes of protests.
OTOH, if only 12% of complaints see corrective action, with less than 3% actually sustained (the others remedied before action is needed), then 88% of complains are bogus, even if those are only 0.3% of overall contracts issued.

So yeah, it certainly looks like people complain far too easily, especially on these really big contracts. The fact that the Army reserved time in the process certainly points to the fact they knew that a protest was inevitable.
 
I also wonder if people doing such things take the time to consider how such will play out for future relationships even if they are successful. After all, one will have to work with the team that you just publicly told made the wrong decision...
If that is factored into future competitions then surely that's grounds for protest in itself
 
I also wonder if people doing such things take the time to consider how such will play out for future relationships even if they are successful. After all, one will have to work with the team that you just publicly told made the wrong decision...
If that is factored into future competitions then surely that's grounds for protest in itself
I think that "the protest" has become a part of the process, especially for the larger contracts. As mentioned it has become a sort of last check before execution of a contract and for the most part appear to validate the government decision.
I am not a fan of this added step in the process, but it does give bureaucrats something to do.
 
The actual number of protests received by GAO and the CoFC is significantly less than during the Cold War, under a thousand cases annually.
Note: the fact that there re fewer cases today doesn't mean much. There are fewer *programs* today than during the Cold War. Honestly, when was the last time the Army fired up a new transport helicopter program? The Black Hawk in 1976?
 
Yeah, its almost as though these days Defense contracts have an additional round: Determine requirements - RFI/RFP/RFT - Responses submitted - Evaluation - Announcement of winner - Deal with Legal Challenges - Negotiate - Enter Contract. Sigh.... :rolleyes:

I also wonder if people doing such things take the time to consider how such will play out for future relationships even if they are successful. After all, one will have to work with the team that you just publicly told made the wrong decision...
If that is factored into future competitions then surely that's grounds for protest in itself
I think that "the protest" has become a part of the process, especially for the larger contracts. As mentioned it has become a sort of last check before execution of a contract and for the most part appear to validate the government decision.
I am not a fan of this added step in the process, but it does give bureaucrats something to do.
As a former officer, trained in DoD Acquisitions, it's helpful to remember the right/ability to protest is a statutory part of the process there to ensure fairness and adherence to process, it's part of what we were trained. Also, something that's stuck with me ever since was when our instructor, who was part of many programs/competitions with a few protests thrown in, mentioned that not every protest is an attempt to overturn the results. Sometimes protests are done to gather information to improve future proposals, a very clear possibility with FARA still out there...
 
Yeah, its almost as though these days Defense contracts have an additional round: Determine requirements - RFI/RFP/RFT - Responses submitted - Evaluation - Announcement of winner - Deal with Legal Challenges - Negotiate - Enter Contract. Sigh.... :rolleyes:

I also wonder if people doing such things take the time to consider how such will play out for future relationships even if they are successful. After all, one will have to work with the team that you just publicly told made the wrong decision...
If that is factored into future competitions then surely that's grounds for protest in itself
I think that "the protest" has become a part of the process, especially for the larger contracts. As mentioned it has become a sort of last check before execution of a contract and for the most part appear to validate the government decision.
I am not a fan of this added step in the process, but it does give bureaucrats something to do.
As a former officer, trained in DoD Acquisitions, it's helpful to remember the right/ability to protest is a statutory part of the process there to ensure fairness and adherence to process, it's part of what we were trained. Also, something that's stuck with me ever since was when our instructor, who was part of many programs/competitions with a few protests thrown in, mentioned that not every protest is an attempt to overturn the results. Sometimes protests are done to gather information to improve future proposals, a very clear possibility with FARA still out there...
A fair point. If the US DoD adhered to it's own rules and policies more often, I suspect we would have a far better feeling about the process. Mid-tier officers are the most notorious at not knowing or neglecting the process. My cynicism of the bureaucrats that abound in the US DoD can cloud my judgement.
 
As a former officer, trained in DoD Acquisitions, it's helpful to remember the right/ability to protest is a statutory part of the process there to ensure fairness and adherence to process, it's part of what we were trained. Also, something that's stuck with me ever since was when our instructor, who was part of many programs/competitions with a few protests thrown in, mentioned that not every protest is an attempt to overturn the results. Sometimes protests are done to gather information to improve future proposals, a very clear possibility with FARA still out there...
A fair point. If the US DoD adhered to it's own rules and policies more often, I suspect we would have a far better feeling about the process. Mid-tier officers are the most notorious at not knowing or neglecting the process. My cynicism of the bureaucrats that abound in the US DoD can cloud my judgement.
@yasotay an understandable perception given tone and content of most press reports on this matter. This is where it's helpful to remember all services run their acquisitions corps differently, we can discuss the civil service types separately. The Air Force has their career acquisition officers mostly start from the very beginning as 6X officers. While other services only bring officers over after a set amount of time or assignments. Some officers from those other services spoke positively of it since they told me that observed AF acquisition types tend to know the regs better than their officers did. The downside is that AF acquisition types have less operational background/experience than officers from other services.

Which is not to say the AF doesn't have a few field grade types who didn't start as 6X officers. Sometimes they're the trash dumped from operations because their MDS/career field went away, or the aircrew/coneheads don't want to let them near an aircraft/ICBM anymore. Personally, I worked for one of them, an O-4 launch operator, who's career field went away since we bought a launch service instead of rockets. Real piece of work who thought because his job title covered contract management it meant the contractor had to do whatever he said, he also said it was a waste of his time to complete mandatory acquisition training. He thought it was insubordinate to explain to him that any direction given outside of the contract SOW was a violation statute, the FAR, DoDI, AFI and could land him in jail. Just to be clear, I'm not a crusader easily offended by anyone who doesn't follow the rules, but the guy was a snake who would have blamed me or one of his Lt's if he got caught.

Then again for the most part the AF system was mostly set up well enough that guys like that were the exception.
 
@mkellytx - I have to agree that the USAF has far better acquisition officers for the reasons you mention. USMC, with USN parental support, seem to be able to go straight to Congress and get a check for whatever. Probably a perception on my part, but I have been told of "tank meetings" where USMC went in with scant detail for the expected briefing and walked out with approval first time.

For the US Army the officers are usually in the Pentagon, or other locations, in a holding pattern for other jobs. They go in with zero training, which is rectified over time, but have no where near the familiarity with OSD and the other agencies. Some of course are just as arrogant as you mention, which is not helpful at all. The "mid-tier" I was speaking of where O-6 and O-7 who feel they have made the grade and are not subject to the rules of mortals. These are exceedingly dangerous and I have seen a number of programs derailed due to their arrogance. Of course there are plenty of good ones too. My frustration is that the methodologies are sound. If we would just use them we would have less turbulence. That said I do think that for large budget acquisition programs, protest are a given, no matter how well the procedure is followed . This might be a good thing, but it does slow the program which can mean higher cost.

I am hopeful that the FLRAA protest will be disapproved by GAO at an early date, but given the size and ramifications of the program, I suspect it will be late March at best for a decision.
 
Interesting press release from Boeing re: FLRAA protest. Notice the careful wording.

Boeing Press Release, Arlington VA, 28 December 2022: Sikorsky, a Lockheed Martin company, filed a formal protest today asking the US Government Accountability Office (GAO) to review the US Army’s decision on the Future Long-Range Assault Aircraft (FLRAA) contract.

Boeing supports the protest filed by our Team DEFIANT partner, asking the GAO to review the Army’s decision.

Based on a thorough review of the information and feedback provided by the Army, Lockheed Martin Sikorsky, on behalf of Team DEFIANT, is challenging the FLRAA decision. The data and discussions lead us to believe the proposals were not consistently evaluated to deliver the best value in the interest of the Army, our Soldiers and American taxpayers. The critical importance of the FLRAA mission to the Army and our nation requires the most capable, affordable and lowest-risk solution. We remain confident DEFIANT X is the transformational aircraft the Army requires to accomplish its complex missions today and well into the future.
 
Sometimes protests are done to gather information to improve future proposals, a very clear possibility with FARA still out there...
I would have thought there are better ways to do that such as debriefs post award.
Unfortunately, not under the current system. Post debrief, short of a protest the government is under no obligation (usually) to share further information. If the contractor doesn't receive the information they want/think they should receive, then they must decide if they want to protest to get it. Contractors have little influence over debriefs, that's up to the government, unless the contractors wish to lobby congress to reform the process and place more specific requirements on the DoD on what they must divulge post award.

I've seen both sides now, things tend to go most smoothly when both parties communicate often, clearly and honestly and when the rules are written down, clear and consistent. Take any of the above away and bad stuff happens.
 
Unfortunately, not under the current system. Post debrief, short of a protest the government is under no obligation (usually) to share further information. If the contractor doesn't receive the information they want/think they should receive, then they must decide if they want to protest to get it. Contractors have little influence over debriefs, that's up to the government, unless the contractors wish to lobby congress to reform the process and place more specific requirements on the DoD on what they must divulge post award.
Ah the differences in different countries systems - I much prefer the systems in Australia...
I've seen both sides now, things tend to go most smoothly when both parties communicate often, clearly and honestly and when the rules are written down, clear and consistent. Take any of the above away and bad stuff happens.
Agree 100%!!!
 
Ah the differences in different countries systems - I much prefer the systems in Australia...
Indeed, as someone married to a Canadian, I am not unfamiliar with the Commonwealth, but there is a bit of difference in size/scope.

The word Byzantine is often used to negatively describe the US system. However, the eastern empire did outlast the west by nearly a millennium...
 

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