Airborne Early Warning & Control: News & Discussion

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SaiK
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Post by SaiK »

Are we thinking about targets like Raptors to be countered with our AWACS? What are the strategies?
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Post by Vick »

In the first pic, one can clearly see the addition of the belly fairing to the aircraft.

Added later: Also, in the first pic, notice the fat tail section. Definitely something going on there.
Last edited by Vick on 20 Feb 2008 03:07, edited 1 time in total.
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Post by JCage »

K Prasad,

Anything in specific about :

- Rajendra
-LRTR/ MFCR
-MMR

Any more pics etc of pvt or public firms..
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Post by k prasad »

JC,

No word on the MMR or LRTR. They were all keeping their mouths shut on that one. What little info I got, I'm not sure if it would be a good idea to post it on the internet. However, the radars are working great, and are much better than the Greenpines themselves, both in range as well as max. Velocity.

As for the Rajendra, much of the same info as has come out n the press recently. Its been upgraded, and they are putting it on a T-72 Chassis. Didnt ask much about Rajendra though.

Also, they're looking at how to make the WLR compact, possibly by cutting it up and putting on 2 vehicles - the Army wants something that can be mobile in the mountains, which the 8x8 Tatra cant do as yet. Same with the other vehicles and radars.

as for the AWACS.. I also noticed the fat tail section. didnt notice it then, which I regret. Anyone has an idea about what it could be... methinks its a fin sort of.
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Post by JCage »

Hmm fair point about the WLR, but iirc its fairly compact as is. Perhaps they want to break it up into a trailer towed by another truck with the power eqpt, and the processing eqpt in another truck. BTW, check mail.
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Post by Vick »

k prasad wrote:as for the AWACS.. I also noticed the fat tail section. didnt notice it then, which I regret. Anyone has an idea about what it could be... methinks its a fin sort of.
Not the fins, the fat conical section aft of the fins.
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Post by Singha »

probably LRMP style extra comm antennas, avionics bays or a bigger APU to
run the electronics on-ground before the generator trolley arrives.

wouldnt the IAF create a hue n cry about the +- 60 angle ? leaves 60' of blind spots in front and back
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Post by Anujan »

Singha wrote:probably LRMP style extra comm antennas, avionics bays or a bigger APU to
run the electronics on-ground before the generator trolley arrives.

wouldnt the IAF create a hue n cry about the +- 60 angle ? leaves 60' of blind spots in front and back
Usually such things are SATCOM links. atleast it is the case with the P-8i
Image

For a full 360 Deg coverage, they need to go in for a radome, not very aerodynamic for a small craft like the embraer. Atleast the front will be covered by a nose-section radar installation IMHO.
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Post by sunilUpa »

Vick wrote:
k prasad wrote:as for the AWACS.. I also noticed the fat tail section. didnt notice it then, which I regret. Anyone has an idea about what it could be... methinks its a fin sort of.
Not the fins, the fat conical section aft of the fins.
Like in LRMP? That would be MAD. But why AWACS would have MAD?
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Post by Vick »

It's definitely not a MAD. I think it's more like rear facing ESM sensors.
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Post by sunilUpa »

Vick wrote:It's definitely not a MAD. I think it's more like rear facing ESM sensors.
Ya, MAD is in the form of a boom. All Emb-145 AEw&C have it. See the pictures here and the line drawing here
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Post by vivek_ahuja »

Guys,

let me add my two bits here:

What you must have noticed is that the standard ERJ-135 have no ventral fins located in the aft fuselage. However, with the addition of the AEW radar, the structure is modified to accommodate two small ventral fins for aerodynamic stabilization (to compensate for the overhead AEW radar structure)

This is what we expected in the initial indigenous AEW aircrafts. This fins are small aerodynamic surfaces only and require very little structural modifications.

However, what the recent model at Defexpo suggests is that there has been substantial ventral fuselage modifications to accommodate what is in good possibility an evolved canoe fairing. This means that the installation of the antennae of the Synthetic Aperture Radar fairing is being considered in addition to the AEW radar.

This changes things substantially, and you have to compensate by adding further ventral fins or increasing the size of the existing pair. This is also what we have seen in the model.

Now, increasing the size of these fins means that you have to compensate for the aerodynamic loading, and that increases the aft fuselage structure accordingly, hence the 'fattening' of the area. It also means that with this increase in size and weight, you can also use the fins to accommodate High-Frequency aerials and host the associated equipment in the fattened area along with the structural reinforcement members. It will also be used to stabilize the aircraft's center of gravity that has shifted to the front fuselage by the addition of the canoe fairing.

Also, the reason it cannot be a MAD is that the detection ranges for a MAD is of the order of half a kilometer or so from the boom location, forcing the aircraft to fly low and perform quick maneuvers/turns to achieve acquisition. The ERJ-145 series aircrafts are too fast and too small to perform this kind of acquisition. Further, the limited range of the MAD means that you would need another source of initial detection to be available in the aircraft, and that is impossible to do unless the aircraft is stripped of all other systems like the radars etc.

-Vivek
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Post by Singha »

a P8 + E3 + E8 would be a killer pakplane combo though. kills all birds with
one stone. hang a half dozen NSMs off the wings and a four Nirbhay on
overwing pylons and it reduces need for MRCA also :rotfl: could also tow
a glider (wooden horsa of ww2 fame) behind carrying a couple of A3 rigged
for airborne launch.
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Post by k prasad »

JCage wrote:Hmm fair point about the WLR, but iirc its fairly compact as is. Perhaps they want to break it up into a trailer towed by another truck with the power eqpt, and the processing eqpt in another truck. BTW, check mail.
got the mail boss.. check urs.

More than compactness, the Army is worried about mobility, especially on the Mountainous roads, which the 8x8 Tatra isnt really suited for (from what I was told).

the Power source is in another vehicle. They're looking at splitting the radar and signal processing units from the control unit, and putting them on separate, smaller vehicles.

I also asked about a Tracked version for the WLR, since a wheeled one wont be able to keep up with the Tanks, travel offroad or in the desert for long. They're looking into doing that as well, but their first priority is getting the WLR into service first.
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Post by sunilUpa »

Ok...here you go, all about Indian AEW&C, from the horses mouth (Dr S Christopher, Director, Centre for Airborne Systems, Bangalore)

Sentinel of the Indian Air Space
In the early days of waging wars, the Chinese army sent up a soldier on a giant kite to observe enemy positions from some height and the air-borne observer continually shouted down his alerts to the commander on the ground, who then quickly ordered the countermoves to his troops. This clever ‘Air-borne
Early Warning and Control’ (AEW&C) concept has come a real long way since then – thanks to the technology explosion in the fields of Radar and Communication Engineering. With its ability to sense
the war situations in air-to-air and airto- surface, all-weather, day and night deployments, the modern AEW&C system has come to be regarded as a powerful ‘Force Multiplier’ in today’s military tactical
operations. The prime functions of the AEW&C system are three, viz., sensing the threat scenario, providing early warning to the friendly forces and enabling initiation and execution of counter-measures and
counter-threats, all in real-time. Actually, the most important facet of the AEW&C system is that it has the potential to stop a war even before it gets around to be started!
While 28 countries are known to have acquired the AEW&C capability, more countries have launched programmes to obtain tailor-made AEW&C systems to augment defence preparedness as perceived in their individual military context. A number of AEW&C systems are being built on a variety of platforms, like aerostats (balloons/airships), unmanned air vehicles, helicopters and fixed-wing aircraft - both big and small. While a good number of systems are operational, the efforts continue to build a variety of systems that are at various stages of development and production all over the world.

The Indian AEW&C
The Indian Defence Research and Development Organisation (DRDO) have launched an AEW&C programme that is focussed on the needs of the Indian Air Force. The Centre for Air-Borne Systems (CABS) of the DRDO that is tasked with the development of the system is pursuing the
programme with participation of multiple work-centres from within DRDO as well as Industries in the Public and Private Sector. The Indian AEW&C system will detect, identify and classify threats present in the surveillance area and act as a Command and Control Centre to support Air Defence operations. The system with its multiple Communication and Data Links can alert and direct fighters against threats while providing ‘Recognizable Air Surface Picture’ (RASP) to commanders at the Ground Exploitation Stations (GES) that are strategically located. The AEW&C system can thus support Air Force in offensive strike missions and assist Forces in the tactical battle area. What is more, the AEW&C system also comprises Electronic and Communication Support Measures that can intercept and counter unfriendly radar transmissions and communication signals.

Primary Surveillance Radar
The primary sensor for the AEW&C will be an Active Electronically Steered Array Radar with a normal detection range and an extended range against a target Radar Cross Section (RCS) of the fighter class
of aircraft. Two radiating planar arrays assembled back-to-back and mounted on top of the fuselage in a Dorsal Unit (DoU) will provide coverage on either side of the DoU. The important modes of operation of
the system are the sea surveillance and the air surveillance. The sensor has the abilities to search, track-while-scan, priority tracking, high performance tracking, etc. In priority tracking, the targets will be placed in full track mode even if it crosses the primary surveillance area. In high performance tracking, additional measurements will be made to improve the tracking accuracies. Utilising the active aperture technology, the radar provides a fast-beam agile system that can operate in several modes concurrently.


Secondary Surveillance Radar
The Secondary Surveillance Radar (SSR) system, or the Identification Friend or Foe system, determines whether the target detected by the Primary Radar is a ‘friend’ or ‘foe‘. The interrogator emits a message querying the target in a particular sector. Replies from the target are automatically associated with the Primary Radar detections. This information is then used by the AEW&C system to identify locations of friendly and unfriendly aircraft in the area and deal with them appropriately.

Mission Communications System (MCS)
The Mission Communications System provides Air-to-Air V/UHF voice and data channels. It also provides for integrated control of all on-board communication sets and intercom for the entire mission Work Station
Operators as well as the flight crew. The communication channels have in-built ECCM features as well. The various segments of the total operational system in the air and on the ground would have a multi-service standardized data link structure that enabled communication among the AEW&C Systems, other AWACS aircraft, the Fighter/Interceptor aircraft and the Ground Exploitation Systems..

Electronic Support Measure (ESM) and Communication Support
Measure (CSM)

The ESM and CSM systems will support suppression of hostile air defences. This will be achieved by performing the surveillance of the environment for detection and identification of hostile emitters of both communication and non-communication types. Towards this, the ESM system operates over a wide range of frequencies with complete coverage of 360° in azimuth and -15° to 5° in elevation. The ESM thus provides the bearing and the location of the hostile emitters to augment the Primary Radar performance. The system is capable of analyzing and identifying the emitter characteristics with a frequency accuracy of 1 MHz
and a directional accuracy of 2° (rms). An easy search method to scan through the database library of 3,000 emitters would also be a feature of the ESM. The system also has the capability to record and save the data for post-flight analysis. The CSM system shall intercept the communication signals and perform the required analysis for in-flight operations. It additionally records the signals on-board for post- flight analysis.


Self Protection System (SPS)
The AEW&C system will have a Self Protection sub-system. The SPS shall consist of Radar Warning Receiver (RWR), Missile Approach Warning system (MAWS) and Counter Measures Dispensing System (CMDS). The RWR function will be augmented by the ESM and will consist of the Warner Library and
Display. The MAWS will be a passive UV based system and, augmented with the RWR, will give necessary warning to the pilot to appropriately activate the CMDS. It provides the essential displays to the pilot and helps in the activation of the CMDS as well as adoption of escape maneuvers for self-protection.

Mission System Controller (MSC)
The Mission System Controller will integrate the information from all the above-mentioned sensors. Its functions include system controls, mission modes, functional control logic, redundant array of independent disks (RAID), database management, integrity function, multi-sensor data fusion, health monitoring, time synchronization, bus control and other housekeeping functions. In addition, MSC will carry out the intercept control functions. MSC will interface with the DHDS system for all operator control and display features.

Data Handling and Display System DHDS)

DHDS will facilitate mission system operators to interface with the AEW&C system. The AEW&C system will have Operator Work Stations for Surveillance, Interception, and ESM & CSM functions. All the consoles can be reconfigured as required. In general, menus, displays and other
presentation logic can be performed by each console. The consoles also help in planning of the mission with communication information handling, weather data handling, mission data preparation and handling.
Data Links
The AEW&C system will be capable of interoperating with other AEW&C systems, fighters, and AWACS aircraft in the air and other earlywarning and air-defence systems on the ground. The data from the Radar, ESM and CSM can be down linked to the ground stations and the tactical
control data up-linked to the AEW&C system. To this end, the AEW&C system will communicate to the Ground Exploitation Stations through ‘C’- Band Data Link and SATCOM. The Data Links will operate with two voice channels.
Aircraft Platform
The Aircraft platform to house the AEW&C System should have the matching flight performance attributes to facilitate that the Mission System tasks are performed effectively during the operational missions. To facilitate extended operations, the endurance of the aircraft can be augmented by an In-Flight Refuelling system

Conclusion
The AEW&C System will boost the Air Force’s Air Operations Capability. The System is multidisciplinary and complex and is projected to be designed, developed, tested, certified and inducted into service in an optimal timeframe. Indigenous development of the Indian AEW&C means three things to the Nation: (i) Air Force is getting a system that costs a fraction of the price of a comparable system in the world market, (ii)
the indigenous capabilities being generated in terms of technologies and infrastructure will be an assurance against technology denials by bigbrother nations and (iii) the ‘feel good’ factor of becoming one among the select group of Nations who really have the wherewithal to make
a machine of this kind.

The adversaries of India should soon be nervous even to warn their forces, ‘Keep off and keep quiet, the Indian AEW&C is on the prowl’, as they would know that the Indian AEW&C would be watching,
sensing and listening to whatever happens in its domain! Globally speaking, it seems possible that AEW&Cs around the planet Earth can bring about a World Without War, or, nip the war in the bud, if
ever someone thoughtlessly triggered one.
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Post by sum »

How much part of all the listed features is already done and whats the percentage remaining(i.e, how far are we from an actual flying Indian AE&W plane)?
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Post by Rudranathh »

There is even a picture of the plane with servicemen at the consoles.
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Post by A Sharma »

Posted on Key Publishing forum
India's first A-50I at Beriev's Taganrog site prior to delivery to IAI for fitting out

Image

Image
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Post by sunilUpa »

^^Press release form Beriev,
No. 122 dt. January 21, 2007.
--------------------------------------------------------------------------------



On the 20th of January, 2008 "EI" airborne early warning aircraft was ferried from Taganrog to Israel to undergo further activities on the installation and testing of the mission system. As planned, the aircraft shall be delivered to the End User this year. AEW aircraft ("EI") is built for a foreign Customer pursuant to a contract awarded by the Federal State Unitary Enterprise "Rosoboronexport".
Currently Beriev Aircraft Company continues the activities under the Contract.


link

They got the date of press release wrong..
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Post by Singha »

http://widebodyaircraft.nl/il76avie.jpg

the regular IL76 doesnt have the line of antennas on top of the vertical
tail. its where the porthole exists for repair person to climb up...was shown
in natgeo mki contest

even our IAF birds dont have it
http://www.airshows.org.uk/2007/airshow ... il76_1.jpg

I think some dorsal antennas are relocated to up there for better reception
and avoid the radar.
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Post by viveks »

I thought that the circular dome is going to be absent in this case as with the regular phalcon. The phalcon has AESA which is electronically steerable.....why this dome?

If this is true then I would suppose then that the configuration given to us would not be upto the standard currently used by the isreali air force.....I may be wrong though.....they have not released the capabilities of the configuration that we will be getting.
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Post by gopal.suri »

:P probably IAF got the old brochure.
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Post by sunilUpa »

viveks wrote:I thought that the circular dome is going to be absent in this case as with the regular phalcon. The phalcon has AESA which is electronically steerable.....why this dome?

If this is true then I would suppose then that the configuration given to us would not be upto the standard currently used by the isreali air force.....I may be wrong though.....they have not released the capabilities of the configuration that we will be getting.
The 'Dome' will not rotate. It will have 3 arrays of Radar arranged as a triangle. See the last page.

edit...some had posted a schematic of array arrangement, I am not sure in which thread (had assumed that it was in this thread)
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Post by negi »

viveks wrote:I thought that the circular dome is going to be absent in this case as with the regular phalcon. The phalcon has AESA which is electronically steerable.....why this dome?
Well it's already been disussed on BR..anyways as you say it's a dome (radome to be precise) and not a 'rotodome' (like one sees on the E-2 Hawkeye).

That is the radome is merely there to protect the aesa elements from weather and at the same time offer a low drag aerodynamic structure.
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Post by Singha »

it will be a equilateral triangle with one side facing the front and opp vertice pointing to the tail..along axis of fuselage. each panel could be twice the
number of cells as the ereyie as the dome permits larger volume.

someone was claiming old airframes refurbished but primer of yellow
suggest brand new puppy. production of IL76 has to be ongoing to satisfy
the chinese order of 35...there cant be that many unfinished shells lying
around.
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Post by Aditya G »

IIRC these were uncomplete airframes lying at Tashkent factory. Even our IL-78s are from that lot.
Singha wrote:it will be a equilateral triangle with one side facing the front and opp vertice pointing to the tail..along axis of fuselage. each panel could be twice the
number of cells as the ereyie as the dome permits larger volume.

someone was claiming old airframes refurbished but primer of yellow
suggest brand new puppy. production of IL76 has to be ongoing to satisfy
the chinese order of 35...there cant be that many unfinished shells lying
around.
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Post by Cybaru »

Excellent. Yes its perfect.

Bulbous nose and other side fairing designs need a lot and lot of shielding. Here shielding is shaped and easy to apply for this design.
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Post by MN Kumar »

The engines seem to be bigger.
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Post by p_saggu »

Phalcon's Radar Array

Image
Image
Last edited by p_saggu on 08 Mar 2008 09:59, edited 1 time in total.
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Post by Singha »

I was told the range of a AESA is somewhat proportional to its diameter "aperture"...hence in that case wouldnt a rotating AESA array (two faced)
inside the dish permit using the full diameter than the fixed array? like
the E3 radar, the height of the array would decline as it nears the edges
but be 5ft tool in the center
:twisted:
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Post by negi »

MN Kumar wrote:The engines seem to be bigger.
Yes they are.. for the older variants had turbojets while the new ones are powered by HB Turbofans.
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Post by Vick »

Singha wrote:I was told the range of a AESA is somewhat proportional to its diameter "aperture"...hence in that case wouldnt a rotating AESA array (two faced)
inside the dish permit using the full diameter than the fixed array? like
the E3 radar, the height of the array would decline as it nears the edges
but be 5ft tool in the center
:twisted:
That is pretty much what the new E-2D does. It puts two arrays back to back and rotates. It can maintain its tracks by "handing off" from one array to the other as they rotate.

The pics of the IAF's future AWACS show clearly why airforces across the world do not prefer to use mil transports for AWACS duties. The Il-76 frame structure and landing gears are designed to lift off and land with 40 tons of cargo. Therefore everything is beefy. In the AWACS role, it will not need even half of the strength that its design permits, meaning it's carrying a lot of dead weight and that reduces flying efficiency and loiter time and increases maintenance. This is the biggest reason for the trend of putting AWACS on efficient civilian platforms. Even the IAF is moving towards that in its homegrown AWACS.
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Post by geeth »

>>>The pics of the IAF's future AWACS show clearly why airforces across the world do not prefer to use mil transports for AWACS duties. The Il-76 frame structure and landing gears are designed to lift off and land with 40 tons of cargo. Therefore everything is beefy. In the AWACS role, it will not need even half of the strength that its design permits, meaning it's carrying a lot of dead weight and that reduces flying efficiency and loiter time and increases maintenance. This is the biggest reason for the trend of putting AWACS on efficient civilian platforms. Even the IAF is moving towards that in its homegrown AWACS.

In that case, why they had to go for strengthening of airframe, instead of 'weakening' of it?

If the weight to be carried is really half the capacity, then the landing gear can be redesigned suitably (to make it lighter) without much effort..

Instead, I for one would use the balance half capacity to carry extra fuel.
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Post by sombhat »

geeth wrote: If the weight to be carried is really half the capacity, then the landing gear can be redesigned suitably (to make it lighter) without much effort..

Instead, I for one would use the balance half capacity to carry extra fuel.
I think the cargo space left after accomodating sensors and crew will be used for extra fuel tanks. AWACS need really high loiter times.
Can the Phalcons be refuelled mid-air? Gurus, anyone?
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Post by nevin »

sure, u see the probe right there on the nose in the pic
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Post by Singha »

civilian aircraft prebuilt 2 deck arrangement neatly fits the AWACS role
having rest areas and consoles in passenger cabin and neat racks of equipment 7 feet tall in cargo hold below.

cargo a/c like IL76 have a tall voluminous open plan fuselage. if you dont
install overhead eqpt racks the cathedral ceilings are wasted. would be
interesting what is the internal arrangement inside our phalcon.

the structural work needed to make a civilian chassis strong enough for
a few extra tons rotodome on its back is less than the penalty paid for
having a super strong cargo rated floor all along the hold, bulbous canoe
fairling for wheels and those high strong wings for rough strips, STOL and heavy loads.
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Post by PaulJI »

geeth wrote:>>>The pics of the IAF's future AWACS show clearly why airforces across the world do not prefer to use mil transports for AWACS duties. The Il-76 frame structure and landing gears are designed to lift off and land with 40 tons of cargo. Therefore everything is beefy. In the AWACS role, it will not need even half of the strength that its design permits, meaning it's carrying a lot of dead weight and that reduces flying efficiency and loiter time and increases maintenance. This is the biggest reason for the trend of putting AWACS on efficient civilian platforms. Even the IAF is moving towards that in its homegrown AWACS.

In that case, why they had to go for strengthening of airframe, instead of 'weakening' of it?

If the weight to be carried is really half the capacity, then the landing gear can be redesigned suitably (to make it lighter) without much effort..

Instead, I for one would use the balance half capacity to carry extra fuel.
The strengthening needed is the same as that needed for an airliner-style aircraft, to mount the radome. The greater strength of the Il-76 airframe is mostly in areas which aren't useful for this role.

High-wing designs are inherently heavier than low-wing, & less efficient in cruise. Better for STOL, rough-field, & providing an uninterrupted through cargo deck. Ideal for military freighters, poor for most other uses.

The cost & time to redesign & re-test the landing gear, & the logistical cost of a new supply chain for a small number of aircraft, is too great to make it worthwhile. Better to use some of that excess capacity for extra fuel, as you suggest.

I've never been quite sure why the Soviet air force decided to use the Il-76 for an AWACS. Perhaps it was because the short-field rough-strip ability was thought useful, for the remoter regions of the USSR.
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Post by PaulJI »

Singha wrote:...
the structural work needed to make a civilian chassis strong enough for
a few extra tons rotodome on its back is less than the penalty paid for
having a super strong cargo rated floor all along the hold, bulbous canoe
fairling for wheels and those high strong wings for rough strips, STOL and heavy loads.
Don't forget the extra weight needed just because it's a high-wing design, which has to have two structures able to support the entire weight of the aircraft instead of only one.
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Post by negi »

Well it's virtually impossible to impress BRFites isn't it.. :)

Yeah even I am for large civilian aircraft being used for the AWACS platform,however IL-76 too isn't a bad choice as the rugged airframe and STOL capability means it can be stationed at small airbases close to the border and in areas like leh/laddakh.

Actually imo IL-76 was a natural choice as any civilian carrier would have meant involvement of Unkil (Boeing) or EU(Airbus) and at the time when the AWACS programme was envisaged I don't think anyone would have thought of US/EU involvement in the programme (especially when Unkil was kind of unhappy with Israeli assistance to India's AWACS programme)
John Snow
BRFite
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Joined: 03 Feb 2006 00:44

Post by John Snow »

http://www.bmrexpress.com/IL76.htm

Probably because of STOL in case of emergency landings (in combat situations ) IL76 could be better?


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During the war in Afghanistan Il-76s flew 14,700 missions. During the time of hostilities, they transported 90% of the troops and 75% of the cargo. Unable to shoot down a high-flying Ilyushin, the rebels tried to damage it at take-off and landing, lying in ambush near major air bases. As a result, Il-76s were often hit by shoulder-launched Stinger and Strela heat-seeking missiles and large-calibre machine-guns. However, the VTA's Il-76s showed a very low attrition rate, thanks to the strong airframe able to absorb extensive damage.
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