Convair Model 49 Advanced Aerial Fire Support System

Orionblamblam

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Abraham Gubler said:
No you mindset is the reason. Same mindset and same reason as to why we don’t have humans living on Mars, global supply of cheap clean energy, dragged the third world through the enlightenment, dragged everyone in the first world through the enlightenment and basically all the good things humans could do but haven’t.

Dude. DUDE! What the hell is wrong here? Do you have some sort of personal investment in this design? There are serious, good reasons why this configuration has not been adopted, and yet you seem to think that it's the result of some sort of worldwide conspiracy... the same sort of looniness we get out of the Burnelli nutjobs.

Just calm the hell down. History is loaded to the gills with designs that never flew, and very rarely did conspiracies and evil mindsets of dumbth have anything to do with it.
 

Abraham Gubler

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Orionblamblam said:
Dude. DUDE! What the hell is wrong here? Do you have some sort of personal investment in this design? There are serious, good reasons why this configuration has not been adopted, and yet you seem to think that it's the result of some sort of worldwide conspiracy... the same sort of looniness we get out of the Burnelli nutjobs.

Just calm the hell down. History is loaded to the gills with designs that never flew, and very rarely did conspiracies and evil mindsets of dumbth have anything to do with it.

LOL. Perhaps the worst thing one can do on the internet is attribute emotion to another poster unless they expressly define how they are feeling. Epic Fail.

In the case of my last point to Colonial Marine I was illustrating the mindset of rejection of difference.

"There is a tendency in our planning to confuse the unfamiliar with the improbable." Thomas Schelling

At no point have I raised or inferred or believe in a conspiracy. Rather that many great things do not rise because they are too different for many small minds. I listed several examples.

As to the “good reasons why this configuration has not been adopted” we have differences of opinion in this matter as expressed in the points above. The attitude expressed by Colonial Marine of it being too different and I don’t like it and so on is what I am railing against.
 

Abraham Gubler

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Orionblamblam said:
Sadly for Air Cav, the VC managed just that. My father's platoon was in a firefight where one of the Hueys was brought down by a giant crossbow... hit the engine, brought the chopper right down. My father examined the bolt... something like 3 to 4 inches in diameter, 10 or so feet long. One of those puppies hit's your bird, you've got problems.

Unless you bird is 49er AAFSS with steel armour resistant to 12.7mm that would blunt even the biggest VC Scorpio (Ed: proper Roman term). Since military helicopters have not been made obsolete on the battlefield thanks to a revival in siege engines I don't think this is a really serious threat.

The 49er's prop may be vulnerable to damage from direct ahead and direct aft but that's better than the rotor heads of all helicopters which are vulnerable to all angle fire except from directly below. Since the pilot can control this limited zone of vulnerability by just not flying right into or away from AA guns its a much, much better surviability issue than a helicopter.
 

Orionblamblam

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Abraham Gubler said:
Unless you bird is 49er AAFSS with steel armour resistant to 12.7mm that would blunt even the biggest VC Ballista. Since military helicopters have not been made obsolete on the battlefield thanks to a revival in siege engines I don't think this is a really serious threat.

Since you previously claimed that such things were outside the realm of reality... couple that epic fail on your part with your epic fail in the realm of basic diplomacy (something that, since even *I* am taking note of it, is something of an achievement) and with your massive, universe-destroying hyperbole, I believe that I can henceforth pretty much ignore any opinion you express. It's a pity, since I *mostly* agreed with you about the Model 49 being a pretty nifty design. But your unwillingness to recognize flaws and downsides smacks more of religious fervor than scientifically rigorous analysis.


For anyone else: I think this Time article from Oct 1965 describes exactly the crossbow my dad's platoon came across (but without the mention of the crossbow having actually succeeded... in 1965, it's not surprising that a little detail like that got left out):

http://www.time.com/time/magazine/article/0,9171,834487,00.html

From Life:
71986857.jpg
 

Abraham Gubler

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Orionblamblam said:
But your unwillingness to recognize flaws and downsides smacks more of religious fervor than scientifically rigorous analysis.

Classic response of a feather ruffled debater. In Australia we call that being a sook. When and where did I deny in a “religious” manner these flaws you speak of? Ohh that’s right rather than instantly agreeing with your nose down belly landing hypothesis I offered an alternative hypothesis considering some other features of the aircraft. To fit your description I would have ignored this issue and stormed on with other statements. But I guess I should have been more ‘diplomatic’ and bowed down at your hypothesis and apologised for daring to meekly offer any possible alternative which of course would have been by private message to avoid any public disagreement.

If you want to insist that the Convair Model 49 suffers from a significant safety shortfall in relation to a conventional helicopter because its three widely separated versus two closely located engines could simultaneously fail or be disabled and/or its enclosed, much smaller propeller system could be damaged versus a highly exposed and large rotor system leading to a failure to utilise its crew ejection system requiring a glide in, belly landing and despite a distended belly lifting the lip of the shroud above the level of a ground and a centre of gravity well behind this lip and even if it did tumble forward the crew are in an armoured, separating capsule removing them from being rolled over inside the breaking up vehicle compared to a conventional helicopter losing its rotor and crashing to the ground with only crash absorbance to save the crew well that’s your point of view freely expressed. However anyone interested in free expression should understand it comes hand in hand with free critique.

Orionblamblam said:
Since you previously claimed that such things were outside the realm of reality... couple that epic fail on your part with your epic fail in the realm of basic diplomacy (something that, since even *I* am taking note of it, is something of an achievement) and with your massive, universe-destroying hyperbole, I believe that I can henceforth pretty much ignore any opinion you express.

Actually that’s not true. I expressed the belief that the ability to shot a crossbow into the shroud of a moving at ~>100 knots (as is the basis of the scenario originally expressed) Model 49 AAFSS is something only fictional Ewoks could do. I mentioned later that such a crossbow would be blunted by the side armour of the 49er. The two are very different engagement geometries. The side the 49er could be hit while the air vehicle is hovering, landed, etc and subsequently be a much easier shot to make.

But heah this is a critique of your opinion as expressed so this must be universe-destroying, hyperbolic, religious, fervored, etc…
 

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I thought I might toss a couple of thoughts:

Placement of center of gravity: Ducted fan tailsitters' stability benefits from a high cg, rule of thumb was higher than the intake lip if possible. My company developed two UAVs using that configuration. On the second one we stuck the engine above the duct for that reason (among others).
We tipped over a couple of vehicles when the legs caught on something on landing. I don't know if castoring wheels would have worked any better.

Control authority: Relies completely on vanes in the exhaust turning the flow. I'd wager that does not grant the same control power as cyclic on a helo. If helos are sitting ducks in a LZ, the -49 would be even more so, as it would take more time to get it moving.

As for relying on armor to survive, I think that's fine for the majority of small arms fire, but if you are ambushed by a dozen guys carrying RPGs, and you are caught in a hover, there isn't much that armor is going to do. I think the AH-64 blunder in Iraq proved that.
That's probably valid for both rotary wing AND ducted fan vehicles.
The amount of hardening require to withstand that kind of attack would eat directly into your useful load weight, something that VTOL machines don't cope with very well because of the increased growth factor (i.e. one extra pound empty weight = 2 extra pounds takeoff gross).

Rather than sitting still and fighting it out relying on armor, I think mobility and moderate amounts of armor results in a more survivable vehicle.
 

Colonial-Marine

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Abraham Gubler said:
Were you? Thanks for letting us know that… You could have been talking about anything to yourself but this is a forum where people talk to each other via clearly communicated words and if you aren’t going to do that just make bold declerations or opinion expecting us to read your mind to know your context then your expectations are a bit misplaced.
Well I apologize for not being precise enough, but I hardly think going into a rant over such a thing is appropriate.

But again the question remains what makes you think it would be hard to hover? Have you consulted Skeets Coleman and Bill Chana on this issue? Assessed their opinions on the matter? Understand the issues of directional thrust hovering compared to rotating wing hovering?

The higher center of gravity more than anything else, that and it would seem that previous coleopter attempts often faced stability problems.

You can believe anything when you don’t know anything about it but there have been plenty tail sitting aircraft which have proven the capacity to transition from vertical to horizontal flight without much aerodynamic problems. The main problem is pilot orientation which of course is solved in the 49er by the articulating cockpit.

And if the articulating cockpit was supposed to solve all of the woes of tail-sitting aircraft, why haven't they been providing CAS for decades now?

As to what makes it easier to hover is that you control your attitude via conventional yaw, pitch and roll controls. With Bill Chana’s throttle vernier control and vertical/horizontal switch between roll and yaw controls hovering is easy peasy. As easy as a helicopter but with all the configuration advantages like pilot view and spatial relationship to the rest of the vehicle.

I don't see why the pilots view being above the rest of the aircraft like that would be an advantage. And some test-flights might be in order before we know if it is as easy to maneuver in NOE flight as an attack helicopter.

There’s your problem there. You seem to think this is some kind of personal contest. It isn’t. So now that you know that can you stop trying to compete as if it is?

I'm not the one who acts as if they've been personally insulted if somebody has a negative view of a certain piece of equipment. You did the same thing when I "disrespected" the MBT-70.

No your mindset is the reason. Same mindset and same reason* as to why we don’t have humans living on Mars, global supply of cheap clean energy, dragged the third world through the enlightenment, dragged everyone in the first world through the enlightenment and basically all the good things humans could do but haven’t.

Its good to know that I am single-handedly holding back the advancement of humanity... Which "enlightenment" do you speak of dragging the first world through? I don't think it is neccessary to mention the problems with nation-building in third world hellholes.

Look at the aircraft from a practical standpoint. What does it do better than a mix of attack helicopters and attack aircraft like the A-10? If you want speed, is the extra costs and risks worth any potential advantage over a compound helicopter design? What about maintenance and logistics? There are obviously real concerns and problems that have prevented aircraft like the Model 49 from becoming reality.
 

Stargazer2006

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Wow. Never expected the Model 49 project could generate such heated debate almost 40 years after its inception!
As to the "conspiracy" question, all I can say is that if I had been a conservative DoD official having to choose between this and the Lockheed Cheyenne, I certainly would have gone for the obvious: a proven type of airframe. That's probably what happened here.
 

Abraham Gubler

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Abraham Gubler said:
Does anyone have any idea what the "WASP Rocket" mentioned in the Convair AAFSS offer is? The limited information says that the centre turret could be equipped with either two 30x113mm cannons with 1,000 rounds for each gun or a single 30mm and 500 WASP rockets. If weight is matched between the options this would mean each "WASP" would weigh about 1kg (2.2 lbs). I would imagine something like the 66mm rocket of the M72 LAW? Google turns up nothing except that the Yugoslavian name for their M72 clone was 'Osa' or 'Wasp'.

By chance I may have stumbled across an answer to the enigmatic nature of this “WASP” system.

The Martin LARA brochure details a WASP II 40mm grenade launcher. This came in either the ASP-1 automatic strafing pod of the ‘Side Firing WASP pod’. These pods weigh 150 lbs with the ASP-1 firing 60 grenades either forward or aft (depending on which way it is mounted) using a revolver mechanism. Three 40mm grenades were mounted in a triangle unit (WASP II) and are fired without the benefit of a barrel, assumedly by a rocket motor. The side firing pod has 78 rockets fixed to fire downwards and is mounted on swivelling lugs.

Judging by the previous imagery of a large revolver type launcher I would assume the WASP (I) as proposed for AAFSS used single 40mm rockets. These weapons would be similar to the SNEB 37mm rocket but using the 40mm grenade as a warhead.
 

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Abraham Gubler said:
By chance I may have stumbled across an answer to the enigmatic nature of this “WASP” system. The Martin LARA brochure details a WASP II 40mm grenade launcher....

Fast forward to 2011 and this would seem like a perfect application for the Metal Storm electronically-fired, stacked projectile technology. Their 3GL grenade launcher uses up to thee individually-loaded 40mm grenades in the same barrel. It's not hard to imagine a pod with clusters a dozen or more of those barrels facing forward, backward, sideways, or downward, perhaps pre-oriented to blanket a large area in just a second.
 

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Mole said:
Fast forward to 2011 and this would seem like a perfect application for the Metal Storm electronically-fired, stacked projectile technology. Their 3GL grenade launcher uses up to thee individually-loaded 40mm grenades in the same barrel. It's not hard to imagine a pod with clusters a dozen or more of those barrels facing forward, backward, sideways, or downward, perhaps pre-oriented to blanket a large area in just a second.

Such an application was featured in many MetalStorm promotional videos. It had two considerable flaws: 1. unlike the WASP the MetalStorm grenade had recoil so a barrage fire would have significant force effect on the aircraft, 2. MetalStorm technology doesn't appear to have meet the levels of reliability and cost effectiveness required for practical use.
 

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Wow.
Like any design this has tradeoffs.

It can hover, albeit not as good as a helicopter, it has better range than a helicopter, but this is not as good as a plane and it is far faster than a helicopter. It can also be used off smaller ships than a helicopter, from a dead amidships flightdeck, albiet with some penalty in topweight if a hangar is included as it is very tall.

I'm wondering if it could be used for Air Sea Rescue. Would the greater rotor wash render that untenable and would the 'possum pouch' compartment be able to accommodate rescuees? Is there anything about this design that would preclude use of a RAST, Beartrap or similar system?

ISTR the French actually flew coelopters, their engineers are not particularly stupid as they are...well....engineers. What dissuaded them from pursuing their design, and if they were technical other than pilot orientation, how did they get addressed by this one?
 

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Hiller also had a Coleopter project in the works. I don't think it's so much that the general layout was flawed, it's just that it's much more difficult to do a folding coleopter type than a straight one. And the Convair AAFSS was to the Coleopter what the Grumman Nutcracker was to the Tomcat. A great idea on paper but likely a white elephant before it could properly see action in an operational way.
 

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I'm not quite where that crack about the French is coming from, but one of the members of this group has written THE book on French coleopters...in French:

La SNECMA, von Zborowski et le Coléoptère
Jean Christophe Carbonel

If you ask nicely, maybe someone will help translate.
 

cluttonfred

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ISTR the French actually flew coelopters, their engineers are not particularly stupid as they are...well....engineers.
That line came off as a bit tongue in cheek, if that was not your intention, my mistake.
 

Mark Nankivil

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Now you can see the Model 49 in film:

http://www.youtube.com/user/sdasmarchives#p/u/91/r6V_LzDVJdo

Enjoy the Day! Mark
 

Triton

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Mark Nankivil said:
Now you can see the Model 49 in film:

http://www.youtube.com/user/sdasmarchives#p/u/91/r6V_LzDVJdo

Enjoy the Day! Mark

Great find, Mark! Many thanks!

http://youtu.be/r6V_LzDVJdo
 

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Thank you, Mark! Amazing footage, with the rare tandem-seat Model 49 (for about two seconds), cockpit mockup and field test footage of LALO drones in the beginning. Worst editing job ever, but who cares?

Also, I want that big model, with all the articulated sections. After watching this film, the factory desk model (shown below) just doesn't do justice to such a radical design.
 

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Stargazer2006

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Some screen captures of the artwork for your enjoyment...
 

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Stargazer2006

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And now the model in straight flight mode:
 

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Stargazer2006

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Some more pics still:

1-4. The model in VTOL mode (cranked fuselage).
5. The LALO test vehicle.
6. The tandem-seater configuration in model form.
7-8. The cockpit mockup.
 

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LowObservable

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I can't look at img32 without the words "EAT LEAD COBRA!" ringing in my ears.

Until I saw the Model 49 I thought that last-days-in-the-bunker Germany had the monopoly of wacky ideas.
 

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I wonder why they chose side-by-side rather than tandem for the cockpit? Wouldn't it have better visibility and block the inlet less in VTOL mode? Cobra was approximately around that time, so at least it wasn't an untrusted cockpit layout for vertical ops?
 

Abraham Gubler

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ouroboros said:
I wonder why they chose side-by-side rather than tandem for the cockpit? Wouldn't it have better visibility and block the inlet less in VTOL mode? Cobra was approximately around that time, so at least it wasn't an untrusted cockpit layout for vertical ops?

Apart from drag the primary advantage of tandem seating is it gives the crew excellent view to both left and right. But unless the cockpits are sharply stepped the rear seater has poor forward vision. Side by side seating gives excellent forward vision for both crew. With these issues in mind I would think they went for side by side to improve their high speed nap of earth flying. Both crew looking forward means for less chance of flying into something. A stepped tandem cockpit would have been a problem to engineer for the 49er because of the need to pivot the nose for the tail sitting attitude.
 

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Abraham Gubler said:
ouroboros said:
I wonder why they chose side-by-side rather than tandem for the cockpit? Wouldn't it have better visibility and block the inlet less in VTOL mode? Cobra was approximately around that time, so at least it wasn't an untrusted cockpit layout for vertical ops?

Apart from drag the primary advantage of tandem seating is it gives the crew excellent view to both left and right. But unless the cockpits are sharply stepped the rear seater has poor forward vision. Side by side seating gives excellent forward vision for both crew. With these issues in mind I would think they went for side by side to improve their high speed nap of earth flying. But crew looking forward means for less chance of flying into something. A stepped tandem cockpit would have been a problem to engineer for the 49er because of the need to pivot the nose for the tail sitting attitude.
I would think that putting that much weight way out on an arm would have presented more stability challenges that they would have wanted to worry about given the state of stability augmentation hardware at that point. Likely would have required a much more robust retraction mechanism as well. That would have been more weight; the nemesis of VTOL.
 

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Greetings all, more lurker than noob so please be kind. I do a lot of paper modeling of all subjects, aircraft a given, and am currently in contact with a master designer of such to make a pattern of the Convair Model 49 AAFSS in 1/48 scale.

Will keep the good members here updated as to the projects progress.
 

Stargazer2006

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patron_zero said:
Greetings all, more lurker than noob so please be kind. I do a lot of paper modeling of all subjects, aircraft a given, and am currently in contact with a master designer of such to make a pattern of the Convair Model 49 AAFSS in 1/48 scale.

Will keep the good members here updated as to the projects progress.

Welcome, patron_zero, and thanks for the info. The Model 49 is an all-time fave of mine, so I'm looking forward!
 

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Now it's a little off topic, but in my view valid in the sense of the design concept of the Model 49 concept!
I found these drawing yesterday on the web. It's the U.S Army's Ordnance Tank Automotive Command (OTAC) Falcon / Aerie program of the 1950's (pre-AAFSS and Model 49)! The Falcon was the VTOL component of the system, armed with 10 x rockets and a 7.62mm machine gun. While the Aerie was the self-propelled mother ship if you would!

Regards
Pioneer
 

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amsci99

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Thanks for the post Pioneer. The Falcon/VTOL component appears to me to be using some sort of a contra-rotating double rotor system. Any members know more about the project?
 

Abraham Gubler

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Robert Bradley’s “Convair Advanced Designs II” has a chapter on the Convair AAFSS (Advanced Aerial Fire Support System) submission (Model 49) that anyone who has followed this thread would know has got me pretty excited. Even without looking at the next chapter on the similar, but different, concept ASW “Localisation And Attack System” (LAAS) shipboard VTOL for the Navy. The book has lots of information on the Model 49 including weights and performance figures and a very nice inboard profile. I thought I would mention some of this new information here and if you excuse me for blowing my own trumpet compare it with some of the predictions I made on this design over the last few years.

Firstly the inboard profile shows that all of the fuel was carried in the central spine of the aircraft between the pivoting crew cabin and the rotor gear box (Convair call it a rotor). The annular wing is practically empty.

As one would expect with an aircraft with four major gearboxes there is quite a bit of oil cooling. These coolers are all located in three of the four fixed cross vanes that connect the central spine to the annular wing. Intakes are on the leading edge and will always have moving air across them when the rotors are spinning thanks to the suction effect. 66% of the oil cooling is for the main rotor gearbox and 11% for each of three right hand turn, main engine gearboxes.

Abraham Gubler said:
Also what is happening to the turbine exhaust? Is it being injected into the duct? There is no easily identified exhaust vent in the pictures of the Model 49 but the engine covers show that they are mounted at the lip of the shroud.

Yes each of the engines is exhausted inside the duct. Between the rotors and the pitch and yaw vanes. Which would make it extremely difficult to see the hot exhaust pipes from outside the aircraft. Significantly lowering the aircraft’s overall IR signature.

Crew escape is detailed and my prediction earlier was wrong:

Abraham Gubler said:
the crew capsule would probably have an F-111 style ejection system enabling the crew to survive the crash.

No escape capsule but each crewmember does have an ejection seat. And the seats were useable in any of the various flight configurations the Model 49 could adopt.

The inboard profile provides plenty of details on the avionics and the weapons magazines which are both plentiful. A 52 point key is provided though I found it much easier to read after scanning at high resolution and zooming in. Sorry spongers but I won’t upload even a low res copy of that scan, go buy the book!

On to weights and Bradley mentions that the Model 49 AAFSS maximum gross weight was 29,500 lbs,

Abraham Gubler said:
Quickly using the McCormick thrust loading formula the Convair Model 49’s propellers and engines (three LTC4B-11s able to produce 3,400 lbs each) should be able to generate around 35,284 lbs of thrust (taking into account an additional 20% efficiency thanks to the ducted fan). The Model 49 is very heavily thrust loaded compared to a conventional helicopter. Meaning maximum takeoff weight of the Model 49 (with the manoeuvre margin) should be about 13 tons (29,403 lbs).

design gross was weight 21,070 lbs and standard payload 2,855 lbs (= 23,925 lbs),

Abraham Gubler said:
For hovering weights an important factor is the ferry requirement. That’s 8,100 pounds of additional, external fuel (four 300 gallon tanks) that must be lifted from a tail sit. Considering a typical weapons payload is about 3,000 pounds (six TOW missiles, 1,000 30x113mm, 500 40x53mm, 12,000 7.62x51mm) that’s a tactical payload surplus of 5,100 pounds. Meaning with full internal fuel and weapons the Model 49 would weigh around 24,300 lbs which is LESS than the thrust generated with only two engines (25,111 lbs).

and the empty weight was 13,965 lbs. So I’m pretty happy with my weight breakdown based on working backwards from the lift potential of the duct and rotor. Hovering was possible at 6,000 feet (95 F standard day) at a weight of 23,700 lbs and at 4,200 feet with the same weight on only two engines! The aircraft was designed to complete the mission on two engines and get home safely on only one if they malfunctioned or were knocked out by the enemy.

Maximum speed was 400 mph (355 knots) at 10,000 feet.

Abraham Gubler said:
The Convair Model 49 AAFSS is not a conventional aircraft. While it would have a high maximum speed, well over 300 knots, it would also have a very low stall speed.

Rate of climb at low altitude (unspecified) was 8,000 feet per minute. AH-64 Apache can climb at 2,500 feet per minute. Range with 2,855 lbs of payload was 450 NM. Ferry range with external tanks and “auxiliary wings” (!) was over 2,400 NM.

The main source given for this chapter was the Convair submission report. Report name and details are given in the footnotes. Two parts of it are:

Model 49 Advanced Aerial Fire Support System Technical Report – Project Definition Phase Proposal, General Dynamics Convair Report 64-300-1, November 1964
Model 49 Advanced Aerial Fire Support System Technical Report – Volume II Planning Purpose Proposal, General Dynamics Convair Report 64-300-4, November 1964

And judging by the code numbers there are at least another two reports out there. Just in case anyone is thinking of visiting an archive and needs a reference.
 

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Such a strange design. Did they really intend for it to land and take on the enemy from the ground and give up it's advantages of speed and manoeuvrability? How much armour did it carry and how proof would it be against an RPG?
 

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Hot Breath said:
Such a strange design. Did they really intend for it to land and take on the enemy from the ground and give up it's advantages of speed and manoeuvrability?



It wasn’t the basis of the capability offer but just something it could do that you couldn’t realistically do in a conventional helicopter. Landing during a mission to provide sustained overwatch of an area is something some militaries do with their scout helicopters and I guess a Model 49 type could do that as well, but better. With the enclosed rotor it could land much closer to local terrain features, de clutch and idle down the engines and get quite a bit of persistence in overwatch compared to flying or hovering. Landing during the middle of engagement is something you really wouldn’t want to do unless for CSAR (crew extraction) or to stop a friendly force being overrun.



Hot Breath said:
How much armour did it carry and how proof would it be against an RPG?



All of the vital features (crew, engines, gear boxes, etc) were to be armoured with dual property steel giving resistance to 12.7mm HMGs. Which is better armour than an M113 APC. An RPG HEAT warhead hit on much of the aircraft would achieve little because it’s the hollow wing. A hit on an engine pod would knock it out but the other two would still be fine. Same for a weapon system. A direct hit on the crew pod wouldn’t be nice but the same goes for any other aircraft.



A lot of these issues have been discussed over the past eight pages.
 

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Abraham Gubler said:
Hot Breath said:
Such a strange design. Did they really intend for it to land and take on the enemy from the ground and give up it's advantages of speed and manoeuvrability?

It wasn’t the basis of the capability offer but just something it could do that you couldn’t realistically do in a conventional helicopter. Landing during a mission to provide sustained overwatch of an area is something some militaries do with their scout helicopters and I guess a Model 49 type could do that as well, but better. With the enclosed rotor it could land much closer to local terrain features, de clutch and idle down the engines and get quite a bit of persistence in overwatch compared to flying or hovering. Landing during the middle of engagement is something you really wouldn’t want to do unless for CSAR (crew extraction) or to stop a friendly force being overrun.

Yet is the one thing that appears most frequently in the illustrations of it. I would suggest landing would be the last thing you'd want to do if it meant it likely the enemy could approach your aircraft and destroy it with a well placed RPG or RPGs. It seems the antithesis of the purpose of using an aerial platform to provide fire support. You lose the advantages of manoeuvrability, speed and surprise.

Hot Breath said:
How much armour did it carry and how proof would it be against an RPG?

All of the vital features (crew, engines, gear boxes, etc) were to be armoured with dual property steel giving resistance to 12.7mm HMGs. Which is better armour than an M113 APC. An RPG HEAT warhead hit on much of the aircraft would achieve little because it’s the hollow wing. A hit on an engine pod would knock it out but the other two would still be fine. Same for a weapon system. A direct hit on the crew pod wouldn’t be nice but the same goes for any other aircraft.
[/quote]

So, it wouldn't be proof against an RPG, which can I believe penetrate substantially more than a 12.7mm HMG? So, we have this large vehicle/aircraft sitting stationary on the ground it isn't substantially armoured? A HEAT warhead hit on the aircraft would more than likely disable it, due to spalling and splinters which have an unfortunate habit of causing considerable secondary damage. A HE hit would more than likely severely damage or destroy it if we are being realistic about matters.

A lot of these issues have been discussed over the past eight pages.

If this was a wunderwaffen, why was it abandoned and never returned to? Perhaps the world moved on and found better solutions to the problems it was meant to solve?
 

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Hot Breath said:
If this was a wunderwaffen, why was it abandoned and never returned to? Perhaps the world moved on and found better solutions to the problems it was meant to solve?

It didn't win the AAFSS competition. Lockheed did. As to why? Well it’s pretty different. Lots of people can't handle the unfamiliar. This was not the first time or last time such a situation arose.
 

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Abraham Gubler said:
Hot Breath said:
If this was a wunderwaffen, why was it abandoned and never returned to? Perhaps the world moved on and found better solutions to the problems it was meant to solve?

It didn't win the AAFSS competition. Lockheed did. As to why? Well it’s pretty different. Lots of people can't handle the unfamiliar. This was not the first time or last time such a situation arose.

Are you sure that objective evaluation might not have found that the Convair Model 49 was inferior to the Cheyenne? It might well have been that it wasn't just unfamiliar but also that it was inferior and the compromises required to utilise it were such that it would not be as effective as a more conventional design (not that the Cheyenne itself wasn't unconventional as well, in it's own way).

Personally, I really cannot envisage something so stupid as attempting to land and then take off again this design in a rice paddy with it's narrow wheels and high weight. It'd sink so far it would be well up to it's arse in mud. I also suspect it's hovering characteristics would be considerably inferior to a helicopter and learning to fly it would be, to say the least difficult and challenging. Not the greatest recipe for success.
 

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Abraham Gubler said:
Hot Breath said:
If this was a wunderwaffen, why was it abandoned and never returned to? Perhaps the world moved on and found better solutions to the problems it was meant to solve?

It didn't win the AAFSS competition. Lockheed did. As to why? Well it’s pretty different. Lots of people can't handle the unfamiliar. This was not the first time or last time such a situation arose.

Actually, there might have been another big factor that you identified in one of your previous posts:

"Maximum speed was 400 mph (355 knots) at 10,000 feet."


From the bureaucratic and sandbox points of view, would Army really want to take on all the fire and brimstone that would come their way from USAF if they said they wanted to develop a vehicle that could do that?
 

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