Register here

Recent Posts

Pages: [1] 2 3 ... 10
1
Early Aircraft Projects / Re: Russian Military Glider Transport Projects
« Last post by hesham on Today at 07:55:43 am »
Artist drawing to Kurbala concept, Козырев - Авиация Красной Армии (Москва, 2011)
2
Early Aircraft Projects / Re: Vakhmistrov composite flying bombs
« Last post by hesham on Today at 07:54:05 am »
In colors; Козырев - Авиация Красной Армии (Москва, 2011)
4
Missile Projects / Re: AIM-120 AMRAAM projects
« Last post by sferrin on Today at 07:53:07 am »
"Typical full-duration VFDR AMRAAM (7-in. class) tests – including pre-fire and post-fire run-ups – required 400 to 600 lbm of air. A block diagram of the facility layout is provided in Fig. 1. Approximately 85% of the VFDR AMRAAM engine tests were performed at this facility. A VFDR AMRAAM ramjet engine is shown on the test stand in Fig. 2.

During a ramjet engine test in the McGregor facility, air from the trailer entered the test facility through a single 3-in. feed line, which then split the flow into two smaller 2-in. feed lines. The air passed through dual-stage pressure regulators to provide a constant pressure to the system, even though the storage tank pressure was diminishing during operation. The regulators also ensured that system pressure never exceeded the design pressure of the pebble bed heating vessels."

Like a nanoscale version of the Project Pluto test setup.  ;D
5
Early Aircraft Projects / Re: Golovin IVS / ISF rocket interceptor
« Last post by hesham on Today at 07:52:09 am »
In colors; Козырев - Авиация Красной Армии (Москва, 2011)
6
Love the way the author conflates the details to make it sound more impressive than it is.  ::)

Not quite sure what point to make other than needless cynicism.

Just that it'd be nice if the media went back to hiring professionals.  But I might as well be wishing to win the lottery.  Anymore you always have to read the fine print for the disclaimers.  "World's largest aircraft!!!!"  Except it's not even close to the largest airship.  As bad as China continually bragging about their "largest seaplane in the world" while the much larger Martin Mars can be seen flying on YouTube.

Well if I wanted to be pedantic you could say we officially don't know how big it is, so it might be the biggest and then again it might not be. ;)

"nearly 200 meters long"
7
Early Aircraft Projects / Re: M.Gudkov’s projects
« Last post by hesham on Today at 07:51:23 am »
From; Козырев - Авиация Красной Армии (Москва, 2011)
8
Missile Projects / Re: AIM-120 AMRAAM projects
« Last post by bring_it_on on Today at 07:50:30 am »
On the VFDR AMRAAM :

Quote
Typical full-duration VFDR AMRAAM (7-in. class) tests – including pre-fire and post-fire run-ups – required 400 to 600 lbm of air. A block diagram of the facility layout is provided in Fig. 1. Approximately 85% of the VFDR AMRAAM engine tests were performed at this facility. A VFDR AMRAAM ramjet engine is shown on the test stand in Fig. 2.

During a ramjet engine test in the McGregor facility, air from the trailer entered the test facility through a single 3-in. feed line, which then split the flow into two smaller 2-in. feed lines. The air passed through dual-stage pressure regulators to provide a constant pressure to the system, even though the storage tank pressure was diminishing during operation. The regulators also ensured that system pressure never exceeded the design pressure of the pebble bed heating vessels.

Each of the smaller 2-in. lines fed an adjustable single-set-point regulator that reduced trailer pressure to a constant intermediate value of choice. Air at this reduced pressure entered a programmable regulator, which controlled air pressure to a downstream metering venturi according to a preset schedule. The dual-stage regulation greatly enhanced the precision tracking of the command pressure profile. Each of the two lines could pass a maximum 11-lbm/sec airflow, thus giving the facility a maximum capability of 22 lbm/sec. The air storage tanks are illustrated in Fig. 3.

The dual airflow lines ran through independent metering venturi stations and through electric pebble-bed heaters. One line dumped air into a heater with a capacity of 1150 R, while the other line ran through a larger heater with a capacity of 1500 R. Piping from the heaters to the test article was electrically heated and insulated to minimize temperature losses. By using different pebble-bed heater temperature set points and mixing air from each of the two lines, the total air flow rate and delivered temperature of the air to the test article was modulated to simulate dynamic flight trajectories. By providing total temperatures up to 1500 R, the facility effectively could achieve Mach 3 sea-level conditions and Mach 3.8 at higher simulated altitude. The large capacity pebble bed heater is shown in Fig. 4.

NEXT-GENERATION PROPULSION REQUIREMENTS


Tactical air-breathing propulsion provides solutions with extended range capability and increased average flight speed. With government added emphasis on time-criticality in next-generation propulsion systems, it became apparent to the NAVSEA/ATK team that the environments would be more severe than what could be simulated by the McGregor facility. During the VFDR AMRAAM program the McGregor facility was consolidated and transferred to the NAVSEA Allegany Ballistics Laboratory site in Rocket Center, WV. It was recognized that the benefits of using a facility arrangement similar to the McGregor storage heated facility would provide accurate clean-air ramjet engine test environments, real-time trajectory capability, as well as cost-effective testing for the end user. Also, by using clean-air methodologies at high pressures, the facility could be widely used to generate data for heat shield and aero- thermal research on materials and flight vehicle airframes.

The facility requirements were defined based on the foreseeable tactical propulsion needs for U.S. interest. The facility was developed to be expandable provided the airflow rate and/or temperature requirements change. But most importantly, the unit had to provide realistic, high-performance airflow to the test vehicle, accurately simulating air-breathing engine flight. The zones identified for near-term need are displayed in Fig. 5.

Three zones were identified that generally encompass the foreseeable tactical propulsion need for ramjet propulsion engines. The first and largest zone represents air-launched missiles, such as VFDR AMRAAM and HARM propulsion upgrades. The second, middle, zone identifies foreseeable improvements to the speed of cruise missile systems such as Tomahawk. The third zone identifies the general region to expect supersonic vehicles that provide kinetic-energy-kill capability such as Future Combat System (FCS), or compact KE missile applications. Figure 5 illustrates a Mach-Altitude flight regime and is overlaid with representative lines of constant total temperature. This provides information as to the temperatures expected in subsonic combustion air-breathing vehicles. Airflow capacity is a function of the engine size, primarily, so the facility was designed upgrade-capable to meet these future needs.

The primary design consideration became the heating methodology. Many forms were considered, including vitiated and storage heaters, but for ramjet engine takeover at low Mach and high altitude, and high Mach flight at high temperature, only the storage heating systems met future high technology evaluation criteria.

10
Postwar Aircraft Projects / Aachen FVA Projects
« Last post by hesham on Today at 07:47:18 am »
Hi,

the Flugwissenschaftliche Vereinigung Aachen established in 1920,continue to this days,the
first project after the WWII was is No.14;

FVA-14 Ring-wing light aircraft,The first project at the FVA after WWII was the FVA-14 Ringflügel, a disc / annular wing aircraft, construction of which began in 1952. Built to investigate the theoretical advantages of a ring wing the FVA-14 was first flown in scale model form, with some success, then wind tunnel tests revealed serious problems with stability which were insurmountable. Work was abandoned and the completed un-flown prototype was stored in a workshop at Aachen where it was broken up to make room for other work.

FVA-15 : this project was instigated to research the use of compressed air for creating control forces om glider wings. Developed by Dr.-Ing. H. Stein the system used air blown through slots over the upper surfaces of a wing to produce lift for control purposes. A Grunau Baby III was modified with roll control slits for testing, retaining normal aileron control for safety purposes. Blown compressed air control systems were found to be feasible, but require a high volume/mass flow air supply to be practical, ruling out their widespread use in gliders.

FVA-27 : Since the Wright brothers started flying at Kill Devil Hill aircraft designers have recognised that canard aircraft are intrinsically more efficient than conventional aircraft and can also have safety benefits. Students at the FVA have initiated a project to design and build a canard glider to meet standard class competition rules demonstrating significant performance gains over comparable standard class gliders. The FVA-27 is a canard glider constructed from CFK (Carbon-fibre/Kevlar) with a welded steel tube truss fuselage structure
Pages: [1] 2 3 ... 10