[Jeroen]

Originally Posted by himanshugoswami

Perhaps something like the Mig 29 which closes its intakes during take off to prevent FOD and uses slats instead?

You need thrust to take off and that means sucking in huge amounts of air somewhere! Usually the engine inlet😀. Slats are found on the wing of some planes and let the wing work at a higher angle of attack.

Not sure about the MIG29, but some aircraft have the ability to alerted the air intake. Eg Concorde, but they use it going supersonic and it's purpose is to slow the air down.

Jeroen

[himanshugoswami]

Originally Posted by Jeroen

You need thrust to take off and that means sucking in huge amounts of air somewhere! Usually the engine inlet😀. Slats are found on the wing of some planes and let the wing work at a higher angle of attack.

Not sure about the MIG29, but some aircraft have the ability to alerted the air intake. Eg Concorde, but they use it going supersonic and it's purpose is to slow the air down.

Jeroen

http://www.team-bhp.com/forum/commer...-rests-us.html

This has some pics that show the closed air intakes while take off an landing. IMHO the fulcrum is unique in this respect and this was engineered to enable it to take off and land on unprepared strips as well

[Jeroen]

Originally Posted by himanshugoswami

This has some pics that show the closed air intakes while take off an landing. IMHO the fulcrum is unique in this respect and this was engineered to enable it to take off and land on unprepared strips as well

Interesting. I find it quite extrodanary it can take off with these inlets closed. Those louvres upon the fuselage look much smaller then the regular intake.

But to your point, this is unique and certainly not the way it works for Tejas.

Jeroen

[Ricci]

Originally Posted by Jeroen

Interesting. I find it quite extrodanary it can take off with these inlets closed. Those louvres upon the fuselage look much smaller then the regular intake.

But to your point, this is unique and certainly not the way it works for Tejas.

Jeroen

The MiG-29 can indeed take off with the main inlets closed, breathing in from the overwing louvres. They're switch open/closed by nose landing gear - as soon the wheel touches down and weight is detected on the front undercarriage, the intake doors shut close ; vice versa, they open on rotation when the nose gear gets airborne. In the event of mechanical failure to open the main doors after take off, the MiG-29 can still operate at up to 800km/h.

Originally Posted by Jeroen

Not sure about the MIG29, but some aircraft have the ability to alerted the air intake. Eg Concorde, but they use it going supersonic and it's purpose is to slow the air down.
Jeroen

Do you mean variable geometry intakes? All supersonic aircraft have to some variable geometry designs - some visible on the outside in the shape of shock cones like the Mirage 2000 or MiG-21 , others like the F-15 or MiG-29 have wedge doors deeper inside the intake duct, not easily visible from outside.

Originally Posted by torquecurve

The point of filling will be different and will mostly have to be located behind the intake to avoid possible ingestion issues and for safety. The intakes also have to be covered while still allowing enough air through for idle power. Being A low bypass engine the cooling systems will also need ducted airflow to ensure that there is adequate cooling.
.

No, the intakes are not covered. Ground crew are directed to maintain safe distance from the intakes, in any case some crew have to be around to direct the pilot for taxiing instructions.

The fuelling port is typically on the underside of the wings, usually closer to wing root than the tip, and often on the side of the fuselage, since most aircraft have wing tanks, and the location is easily accessible. The same port is used for hot refuelling. Startup doesn't take 15 minutes, it's the checks that take time. Aircraft on alert status can be airborne in 5 minutes from cold start, the checks , fuelling and arming are done beforehand though.

[Jeroen]

Originally Posted by Ricci

Do you mean variable geometry intakes? All supersonic aircraft have to some variable geometry designs - some visible on the outside in the shape of shock cones like the Mirage 2000 or MiG-21 , others like the F-15 or MiG-29 have wedge doors deeper inside the intake duct, not easily visible from outside.
.

Yes, they all need to slown down the air into the engine.
Here a nice write up and a little animation on the Concorde engines. Of course, for it's days it was extremely advantaged.

https://www.heritageconcorde.com/air-in-take-system

Originally Posted by Ricci

No, the intakes are not covered. Ground crew are directed to maintain safe distance from the intakes, in any case some crew have to be around to direct the pilot for taxiing instructions.

The fuelling port is typically on the underside of the wings, closer to wing root and fuselage since most aircraft have wing tanks. The same port is used for hot refuelling.

Thanks for confirming.

Jeroen

[torquecurve]

Hey guys - sorry my bad - the intakes need not be covered while taking on the fuel. The wheels are chocked. Safety precautions will of course be in place. My apologies

[SmartCat]

To me, this makes total sense -> large number of Indian jets with average capabilities vs low number of expensive foreign jets.

IAF commits to 324 Tejas fighters, provided a good Mark-II jet is delivered
https://timesofindia.indiatimes.com/...w/63306776.cms

[mpksuhas]

Was able to visit to war memorial in Pune last weekend, its a good place for people intrested in militiary ware and also history of armed conflict in the subcontinent.

Location

At the lawns of the memorial, there is a MiG 23 Bn with the following display-board. It mentions that this was the very same fighter used to bombard Tiger hills during Kargil conflict. Also, it was the last MiG 23 to have flown anywhere in the world.

Excuse the bad quality image from my mobile taken when it was dark.

Originally Posted by smartcat

large number of Indian jets with average capabilities vs low number of expensive foreign jets.

This works out good and make sense in the 42 squadron / two front war debate. I am no analyst, however thinking of a short but intense war, it make sense to have a small but potent number of fighters rather than a bigger number of average capablity fighters.


Sharing an interesting article I came across few days back on this debate, do go through that when you get time.

Link

[Foxbat]

Originally Posted by mpksuhas

Also, it was the last MiG 23 to have flown anywhere in the world.

I don't think this is true, they are being used in the Libyan Civil War:

http://www.defenseworld.net/news/182...k#.WrPnI5NubBI


and some are being used by private individuals:

https://en.wikipedia.org/wiki/Mikoyan-Gurevich_MiG-23

[Foxbat]

Originally Posted by mpksuhas

At the lawns of the memorial, there is a MiG 23 Bn with the following display-board. It mentions that this was the very same fighter used to bombard Tiger hills during Kargil conflict. Also, it was the last MiG 23 to have flown anywhere in the world.

Excuse the bad quality image from my mobile taken when it was dark.

I also took a picture when it was dark, it was at the end of random a 12 hour 550km+ joy ride from Hyderabad to Pune (originally had planned to go to Hyderabad airport) and I stopped when I saw this:



Posting after time limit for editing posts.

[skanchan95]

Originally Posted by Foxbat

I don't think this is true, they are being used in the Libyan Civil War:

http://www.defenseworld.net/news/182...k#.WrPnI5NubBI


and some are being used by private individuals:

https://en.wikipedia.org/wiki/Mikoyan-Gurevich_MiG-23

That's right. Indian AF was not the last air arm to operate MiG-23s.

The SyAAF still operates a decent number of MiG-23MF/MLD and MiG-23BNs against ISIS and other jihadist rebels in their country. Many have been shot down in the conflict.

[V.Narayan]

I think what may have happened is - (i) this was the aircraft that flew the last BN variants flight in India (most likely); or (ii) it was the last BN flight till the Syrian AF took some of its mothballed reserve fleet and put it back into action. Just my guess. The BN was as rugged and trouble free as they come. In fact the MiG-27 that evolved from the BN was recognized by the yanks as the fighter with the best dispatch reliability record in the then Soviet fleet. The world of aeronautics is less rich with the fading away of the MiG bureau to the background.

[mpksuhas]

Originally Posted by Foxbat

I don't think this is true, they are being used in the Libyan Civil War:

Even when you mentioned, I was thinking may the signage was correct since Syrian AF may not be having MIC 23 BN's

However, posts below proves otherwise.

I guess as Narayan mentioned, it may be that Syrian AF got their previously grounded fleet up.

Originally Posted by skanchan95

The SyAAF still operates a decent number of MiG-23MF/MLD and MiG-23BNs

Originally Posted by V.Narayan

or (ii) it was the last BN flight till the Syrian AF took some of its mothballed reserve fleet and put it back into action. Just my guess. .

The BN was as rugged and trouble free as they come. In fact the MiG-27 that evolved from the BN was recognized by the yanks as the fighter with the best dispatch reliability record in the then Soviet fleet

This brings up the question. Why MiG 23's were decommissioned while older MiG 21's still serve IAF? In that sense, which aircraft is replacement of MiG 23's in current fleet of IAF? Since apart from SU 30 MKi, remaining lineup was present when MiG 23 was in service.

Originally Posted by Foxbat

(originally had planned to go to Hyderabad airport) and I stopped when I saw this:.

Well, you stopped at a place where aircraft was there. Atleast that was part of the initial plan too.

[skanchan95]

Originally Posted by mpksuhas

This brings up the question. Why MiG 23's were decommissioned while older MiG 21's still serve IAF? In that sense, which aircraft is replacement of MiG 23's in current fleet of IAF? Since apart from SU 30 MKi, remaining lineup was present when MiG 23 was in service.

The last two IAF MiG-23BN 'Vijay' squadrons converted to or were re-raised on Su-30MKIs - No.220 'Desert Tigers' in 2012 and No.221 'Valiants' in 2017. The third MiG-23BN squadron (No.10 'Winged Daggers') traded their MiG-23BNs for MiG-27s at some point in time and currently fly the MiG-27UPG.

The two MiG-23MF 'Rakshak' squadrons converted to MiG-29 and Jaguar IS(No.224 'Warlords' fly the Jaguar IS and No.223 'Tridents' fly the MiG-29(possibly the UPG variant).

[V.Narayan]

Originally Posted by mpksuhas

This brings up the question. Why MiG 23's were decommissioned while older MiG 21's still serve IAF? In that sense, which aircraft is replacement of MiG 23's in current fleet of IAF? Since apart from SU 30 MKi, remaining lineup was present when MiG 23 was in service.

The Mig-21s that continue in service (also now being phased out) are the MiG-21Bis variant ie the final multi-role version that were built by HAL from roughly 1981 to 1986 (or 1988). They as you may know were upgraded to the 'Bison' configuration with BVR, HMS etc and hence the brains remained fully relevant for todays scenario. The Mig-27ML also underwent a half upgrade (UPG) to keep them relevant into the 2000s. The Mig-23BN did not undergo any significant upgrade of its nav-attack systems to best of my knowledge (happy to be corrected). Two squadrons of Mig-27UPG remain in service I believe. Ultimately our Soviet hardware has fallen prey to shortage of spares on time. Foxbat and Sandesh can add more colour.

Originally Posted by skanchan95

The last two IAF MiG-23BN 'Vijay' squadrons converted to or were re-raised on Su-30MKIs - No.220 ......

Your knowledge is amazing...