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ProjectTech Profiles / Re: The Air Staff and the Helicopter
« Last post by CJGibson on Today at 08:00:53 am »
JFC - having talked to a few of the folk involved in all that AST.404 nonsense, the impression gained is that nobody had a clue what was going on! That was before the politics was factored in. At least it was killed off before it turned into a Nimrod/Phoenix/Atlas-style spinning bow-tie extravaganza.

Chris
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AN INVESTIGATION OF STARTING TECHNIQUES FOR INWARD TURNING INLETS AT FLIGHT SPEEDS BELOW THE ON-DESIGN MACH NUMBER


Quote
The Air Force Research Laboratory (AFRL), in conjunction with the Raytheon, Aerojet and Pyrodyne corporations, has attempted to fulfill an RFP from the Variable Flow Ducted Rocket Flight Vehicle Concepts (VFDR FVC) program. In response to the given guidelines, the group constructed the Mustang II inlet presented in Figure 1; a streamline traced, inward-turning, mixed compression inlet.

Initial CFD analysis of the inlet, by AFRL, at cruise conditions revealed that the inlet held promise in meeting the given RFP. Also, it performed better than the previously designed external compression inlet (9). The CFD analysis, however, was performed on a pre-started inlet operating at cruise conditions. Initial experimental testing, on the other hand, showed that the inlet failed to start under any Mach number and back pressure combination. This initial failure, a common problem for every inlet that relies upon internal compression (or mixed compression inlets that have the majority of the compression done internally), was handled with the current method known to date; bleed holes were drilled at the throat and slightly upstream of the throat and can be seen in Figure 2. The bleed holes were angled toward the free stream and were drilled around the inlet perimeter at both locations.

Unfortunately, this method failed to rectify the starting problem for the Mustang II inlet (9).
AFRL is now in search of starting techniques to assist the Mustang II inlet project. Overall, a generic, simple, and effective starting technique is needed to provide a baseline start-able inlet for any streamline traced, inward-turning inlet (9).

Variable Flow Ducted Rocket Missiles

In the late 1990s, the European Union began looking for a new medium range air- to-air missile to outfit their new Euro-fighter. While many thought they would simply use the American made AMRAAM missile, the European Union decided, in 1995, to fund the BVRAAM project instead (5). The new project called for longer ranges, linear velocity profiles and better guidance systems (5). Traditional missiles, using existing solid rocket technology, could not accomplish the requirements of the European Unionís proposal; therefore, in order to accomplish the design goals, the competing companies turned to VFDR Missiles. In 2000, the European Union awarded their BVRAAM contract to a European contractor and the Meteor Missile, Figure 3, has hence been in development (5)......


The magnitude and complexity of these issues is only increased as the Air Force, Aerojet, and Raytheon (one of the BVRAAM competitors) are now trying to change their design to fit the needs of the United States military; namely the new F/A-22 Raptor (9). Reasons for the increased complexity are found in the unique design characteristic of the F/A-22; a low observable (LO), high speed super cruise fighter aircraft with internal weapon carryout. As can be seen in Figure 3, the external inlet design of the meteor missile is a large bulky rectangular design that affects the placement of the aft control fins. Similarly, the baseline VFDR missile follows the same design mentality (9).


These large rectangular inlets, plus the displacement of the control fins cause the overall wingspan of the missile to increase from 12.5 inches (19) to more than 20 inches (9). This increase then limits the missiles usefulness as the internal weapons bay of the F/A-22 can not accommodate these weapons in their current configuration. The F/A-22 can accommodate six standard compact AMRAAM missiles, but would only be able to carry, at most, four VFDR missiles (9). The guidelines given by the VFDR FVC specifically call for an inlet design that would not increase the frontal area of the VFDR missile and hence make it an acceptable replacement for the current compact AMRAAM Missile.....

https://www.scribd.com/document/349586983/Ada-438398
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Postwar Aircraft Projects / Re: Mil V-16 helicopter
« Last post by hesham on Today at 07:53:04 am »
In my files,

the original or early concept for this beast ( Mi-16) was a super heavy helicopter,powered by 6 D-25VF
engines ?.
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Early Aircraft Projects / Re: Kocherigin LR-2 light recce aircraft
« Last post by hesham on Today at 07:23:24 am »
In Colors.
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Early Aircraft Projects / Re: Nikitin- Shevchenko VG Designs
« Last post by hesham on Today at 07:15:22 am »
Thank you my dear Redstar,

but Mr. Bill Gunston emphasis on IS-3 was existed but never known anything about it.
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Early Aircraft Projects / Re: What the heck is this?
« Last post by redstar72 on Today at 07:15:17 am »

I agree that the thing looks like (and most probably actually is) a rather bad and incorrect mockup of the Ohka 11 made for the museum.
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Early Aircraft Projects / Re: Polikarpov I-16 - origins and development
« Last post by hesham on Today at 07:12:09 am »
From; Козырев - Авиация Красной Армии (Москва, 2011)

a two strange concepts to I-16 ?.
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Early Aircraft Projects / Re: Nikitin- Shevchenko VG Designs
« Last post by redstar72 on Today at 07:08:22 am »

was that a real artist drawing to IS-3,or a misprint ?.

This is a misprint. Actually, this is a picture by B. Kaplunenko representing IS-4 during takeoff, from Modelist-Konstruktor magazine No.8/1975 (the technical drawings attached to the previous reply by Avimimus are from the same magazine). Of course the original picture was colorful. Here it is.

P.S. I've never heard about any Nikitin/Shevchenko project named IS-3; probably it never existed.
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Early Aircraft Projects / Re: Boris Yuriev helicopter and VTOL projects
« Last post by hesham on Today at 07:07:12 am »
The Yuriev Discoplane.
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Early Aircraft Projects / Re: Various Grokhovski projects
« Last post by hesham on Today at 06:52:54 am »
The G-37 & G-39 in colors.
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