LCA News and Discussions, 22-Oct-2013

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Re: LCA News and Discussions, 22-Oct-2013

Postby K_Rohit » 29 May 2014 10:16

Aditya_V wrote:Does "Advanced Weapons Trials" include BVR Missile, say Derby Firing?


Before Derby, would be interested in knowing if the gun has been tested!

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Re: LCA News and Discussions, 22-Oct-2013

Postby merlin » 29 May 2014 12:01

indranilroy wrote:
merlin wrote:No Derby firing as far as I can tell. But perhaps a supersonic drop tank because the article says drop tanks of a new design.

SP1 is delayed, HAL should stop giving out dates.

Would be extremely happy if true. But I think it is the certification of the 725 ltr drop tank in the centerline position.


You are right, this is more likely the case. Still good, all three wet positions are certified for drop tanks.

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Re: LCA News and Discussions, 22-Oct-2013

Postby shiv » 29 May 2014 14:02

K_Rohit wrote:
Aditya_V wrote:Does "Advanced Weapons Trials" include BVR Missile, say Derby Firing?


Before Derby, would be interested in knowing if the gun has been tested!

From the Tarmak link
Ahead of the FOC, crucial milestones that the project needs to complete include, integration of the missiles with the radar, integration of Russian-made 23 mm GSH gun, air-to-air refuelling probe, better braking system and change of nose cone radome from composite materials to quartz for an improved range.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Philip » 29 May 2014 18:34

That's a lot of work left.The gun is vital.Vibration,gas ingestion,etc. may become issues. The report also said that the final config. for the production series was almost at hand and that LSP-1 would roll out soon.

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_26622 » 29 May 2014 23:07

None of these 'to be done' are flying to the moon risk items. Retrofitting and upgrading happen throughout an aircraft lifetime. At least we will be doing locally and priced reasonably (M2000 upgrade - 40 Million $ :eek: , Mig 29 upgrade -16 million $ :shock: )

We need to double down and make 100 LCA's per year at the minimum to make up for our numerical dis-advantage vs. China, replace Mig-21's and 27...

Hoping new leadership splits the order and includes another Indian private player to keep HAL on its toes!

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Re: LCA News and Discussions, 22-Oct-2013

Postby vsunder » 29 May 2014 23:44

Subramanyam is on record that 50% of the work towards in-flight refuelling system is already done. This is in an interview he gave to Ajai Shukla around the time of IOC in December 2013. He claims there are no serious technological challenges ahead. His interview does not mention the cannon. I think the greatest difficulty is integrating the BVR missile. I also thought that FOC entailed raising the angle of attack from 22 degs to 24 degs. The interview makes no mention of this.


Interview with P.S.Subramanyam

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Re: LCA News and Discussions, 22-Oct-2013

Postby srai » 30 May 2014 08:22

shiv wrote:
K_Rohit wrote:quote="Aditya_V" Does "Advanced Weapons Trials" include BVR Missile, say Derby Firing? /quote

Before Derby, would be interested in knowing if the gun has been tested!

From the Tarmak link
Ahead of the FOC, crucial milestones that the project needs to complete include, integration of the missiles with the radar, integration of Russian-made 23 mm GSH gun, air-to-air refuelling probe, better braking system and change of nose cone radome from composite materials to quartz for an improved range.


It would seem "Advanced Weapons Trials" means firing "all the new weapons [IOC qualified 100kg/250kg/450kg bombs, LGBs, CCM, Drop tanks and ECM chaff/flares] in all possible release modes". That leaves two weapons, BVR AAM and 23mm GSH gun, still left to be qualified. Out of the two remaining, gun would probably be the more challenging one.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Uttam » 30 May 2014 17:32

srai wrote:It would seem "Advanced Weapons Trials" means firing "all the new weapons [IOC qualified 100kg/250kg/450kg bombs, LGBs, CCM, Drop tanks and ECM chaff/flares] in all possible release modes". That leaves two weapons, BVR AAM and 23mm GSH gun, still left to be qualified. Out of the two remaining, gun would probably be the more challenging one.


Thoughts of total novice:

Isn't gun on a fighter one of the oldest weapon of last century. I would imagine the developers already have enough know-how on gun integration that this will not be a difficult task.

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Re: LCA News and Discussions, 22-Oct-2013

Postby vsunder » 30 May 2014 19:02

@Uttam^^^^

That is indeed true that the gun/cannon is one of the oldest weapons used on aircraft. But each aircraft has it's own special problems that need to be addressed. Some of the important issues wrt cannons are

1. Smoke and fume ingestion by engines once the guns are fired and consequent loss of performance.

2. Debris in the form of spent shell casings which may be ingested by the engines and/or strike the body of the aircraft at high speeds. This can be lethal. A collection arrangement for the debris has to be thought of.

3. Integration of a potential Russian gun and its attendant electronics with electronics of Israeli and/or software of Indian origin. This should be less of a problem for the BVR with an Israeli radar and an Israeli missile, but not a "no problem".

4. Lastly and very, very importantly: Access to the gun should be very easy for re-arming quickly between sorties by aircrew who are not of the level of a crew chief of a BRD of the IAF and not a DRDO scientist. This will be done in rough conditions at a front line base so the access should be easy and no wires and electronics of the gun must be in the way in re-arming. The interview by Subramanyam mentions a 1 hour turn around time between sorties and this should be aimed for at the end of FOC.

Thus there are issues even with the cannon and they have to be addressed.

One last issue before FOC in addition to various things in my previous post, may perhaps be to replace the nose cone by a "quartz" nose cone instead of the composite one and thus increase the range of the radar in the nose cone. Whether this will be done post FOC or before FOC remains to be seen. I hope this sheds some light, I am also ignorant too.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Uttam » 30 May 2014 19:15

Thank you "vsunder" for a detailed discussion of gun integration. I wonder if parallel teams have already been working on some of the issues you listed.

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Re: LCA News and Discussions, 22-Oct-2013

Postby shiv » 30 May 2014 20:03

There are some great (some funny, some not so funny) stories of what vibration from guns do to aircraft - and many of them Indian aircraft imported from abroad and accepted as having passed FOC. Things getting shaken loose like HUD falling off, and in other cases more serious complications like switches moving from one position to another or canopy flying off.

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Re: LCA News and Discussions, 22-Oct-2013

Postby vsunder » 30 May 2014 20:06

And as Shiv correctly points out, vibration is a also a fundamental problem. In fact in the last semester final exam in diff. equations for second year biology, biochemistry and Chemistry students I gave them a toy vibration problem with damping for the gun of a M-60 tank. One had to find the correct damping constant for the damper for the gun to operate within parameters. The class had many women and they learned about a tank too. Many of them solved it correctly and got full points.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Rahul M » 30 May 2014 22:00

also, the recoil of the gun adds a force that doesn't pass through the centre of gravity of the aircraft and it's very likely the FBW needs to be modified to account for it. Tejas FBW probably has this already but they still need to test it in real life.

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Re: LCA News and Discussions, 22-Oct-2013

Postby vic » 30 May 2014 22:08

HAL has been building SP-1 for around 9 years and still nowhere near flight.

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Re: LCA News and Discussions, 22-Oct-2013

Postby RKumar » 30 May 2014 22:34

vic wrote:HAL has been building SP-1 for around 9 years and still nowhere near flight.


Can you please explain, how HAL can roll out IOC compatible planes 9 years back when IOC was achieved only last year. :(( :(( :((

Whom to blame for this time slippage is another debate, but you are shouting wrong words at the wrong time.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Sid » 30 May 2014 23:51

RKumar wrote:
vic wrote:HAL has been building SP-1 for around 9 years and still nowhere near flight.


Can you please explain, how HAL can roll out IOC compatible planes 9 years back when IOC was achieved only last year. :(( :(( :((

Whom to blame for this time slippage is another debate, but you are shouting wrong words at the wrong time.


Its been 3 years actually.

First picture was reported in 2011 by Shukla ji. http://ajaishukla.blogspot.in/2011/02/j ... -this.html

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Re: LCA News and Discussions, 22-Oct-2013

Postby RKumar » 31 May 2014 02:16

Let me ask another question ... was IAF air marshal ready to accept three legged cheeta?? If not then he has to wait for 3 or 30 years :rotfl: :P

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_26622 » 31 May 2014 03:56

See a lot of judgements been passed on HAL. Remember that their are 150 plus Dhruv in operation. And it is a solid product proven in recent disaster relief operations.

It's time to stop and just start making LCA's on war footing !

Gun or no Gun, BVR ready or not, All of these can be retrofitted easily. This plane has big potential for export (like Dhruv) which can only be done if we get over IAF requirements fast. That to me is the big picture which is sorely been missed.

Hoping Modi Govt sees this and pushes ahead asap for two or more manufacturing lines.

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Re: LCA News and Discussions, 22-Oct-2013

Postby vic » 31 May 2014 10:42

SP-1 and SP-2 are NOT IOC standard aircraft and are on manufacturing line from 2005-7 onwards. HAL is incompetent, corrupt and are liars.

ALH design has nothing to do with HAL. I have posted my views on the subject along with CAG reports a lot of times and have no intention on getting into useless flame war again.

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_22605 » 31 May 2014 14:16

vic wrote:SP-1 and SP-2 are NOT IOC standard aircraft and are on manufacturing line from 2005-7 onwards. HAL is incompetent, corrupt and are liars.

ALH design has nothing to do with HAL. I have posted my views on the subject along with CAG reports a lot of times and have no intention on getting into useless flame war again.


Yes and we guys at RWR&DC have been wasting time and your precious public funds for 30+ years, we have not developed ARIS (Anti Resonant Isolation System)for vibration reduction, we have not almost made a new gearbox after the gearbox that the germans designed broke up within hours, we have not designed and manufactured the most complex composite MRB in service today, we have not developed an extensive knowledge base for composite structures design and manufacturing, we have not developed the most modern helicopter testing facility in the whole of asia, we have not developed the LCH after overcoming the issues of the ALH, we have not designed the LUH (which may again be a world beater in high altitude performance) all by ourselves, we are not developing our control laws for AFCS, we do not have some of the best flight test engineers and daring test pilots, we do not have some of the most innovative research programs for vibration reduction and structural health monitoring, we have not developed a wide and extensive local vendor base, we have not done many other other things which i can describe but you probably won't understand.
Yes we are incompetent(those PhDs and those very exclusive set of helicopter designers), corrupt(people who work for half or less than half the salary that a just pass, regional college passout data entry operator earns) and are liars. Stay happy,
Cheers!

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_23694 » 31 May 2014 15:03

^^^^^^^^^^^^^^^^^
Sir, all the above are definitely great work but what HAL and others lack is in terms of packaging , quality , marketing and communication.

Just check any Dassault , LM, Boeing etc video on youtube , they are fantastic. All this along with a competent product tend to create a perception as if they are all Alien tech. LCA, LCH etc may be good and has potential to be fantastic but do we have any sleek communication package from HAL about it and future plans. Honestly all the videos on Desi product reminds one of old DD documentaries . Even the top leadership of the country believes in communicating , when will HAL and others understand.
If SP-1 and SP-2 has been delayed then HAL should come up with clarification so that all are reassured. F-35 program seems to be more transparent than the LCA program .
BTW with 100% FDI in defence and if the Indian pvt sector join the bandwagon then if HAL does not evolve themselves, then their is a serious chance of a scenario where HAL and others going the BSNL/MTNL way and DRDO working with new private defence enterprises in line with the US way

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_20317 » 31 May 2014 15:47

On gun integration bhailog would enjoy this:

http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=1019

The first in-flight testing of the GAU-8 was done on Feb. 26, 1974. The gun was fired for the first time in flight with combat ammunition on June 19, 1974. The Avenger fired more than 39,000 rounds of ammunition during approximately 60 test flights. The gun was tested in a wide variety of flight profiles: from as high as 25,000 feet to as low as 100 feet; at speeds ranging from 135 knots to 415 knots; in all attitudes (various roll, pitch and yaw) with up to five G's.

The test program went smoothly and the first test mission cancellation didn't occur until Nov. 12, 1975, when the gun jammed. The test program identified a few problems including gun residue buildup on the canopy and problems with gun gas ingestion into the engines. Both problems were solved and fixes were incorporated into production aircraft beginning with aircraft No. 16 (earlier aircraft were retrofitted with the fixes).


The much mentioned 'stopping of A-10 in mid air' is not real but it is said that the throttle automatically is opened up when this gun fires. Then targeting wargeting to hai hi. Guns can only be targeted once unlike AAM.

Most of it is not a worry for LCA but gives you ideas about how the testing is done.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Cosmo_R » 31 May 2014 15:54

nukavarapu wrote: ",,,,,, We had one such divine beauty called 130-J. Even now, nobody has the freaking idea about why it crashed which is hardly a year old. Let them criticize Boeing. I am fed up with this judgmental know-everything smart-a$$ characters.



http://indianexpress.com/article/india/ ... aft-crash/

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Re: LCA News and Discussions, 22-Oct-2013

Postby Cosmo_R » 31 May 2014 16:04

@raghuk, @dhiraj ^^^: No one is blaming the engineers. HAL management is to be blamed. Not the various individuals who have headed it over the years but the structure and its relationship to the MoD and the services. It makes the process of rolling out something almost impossible.

I hope Modi Sarkar will carve up HAL into logical business units that are more manageable, pay engineers and others at market and most important as he has done with bureaucrats in Gujarat, give them goals, freedom of action and reward for success vs. the usual punishment for any action with no upside.

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_19648 » 31 May 2014 16:04

dhiraj wrote:^^^^^^^^^^^^^^^^^
Just check any Dassault , LM, Boeing etc video on youtube , they are fantastic. All this along with a competent product tend to create a perception as if they are all Alien tech. LCA, LCH etc may be good and has potential to be fantastic


Ok so youtube videos and jazzy brochures make a product fantastic, otherwise its only good!!! And why should HAL come up with jazzy videos or presentations just to make fanboys happy. They are doing their work which is good enough and they have better things to do. There is scope for improvement but useless criticism don't help things.

we have not designed the LUH (which may again be a world beater in high altitude performance) all by ourselves


That was a nice nit pick. :D

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_23694 » 31 May 2014 16:37

Ivanev wrote:And why should HAL come up with jazzy videos or presentations just to make fanboys happy


oh sorry, unjustified request/demand from my side. Let the people at HAL do the hard work and create world class product and not brag about it to the world . Who am i to say that branding and marketing is important for the success of a good product . Probably because of a dedicated customer in terms of Indian armed forces they do not need to do it. Neither do they seem to have the ambition to take their world class product and compete in the big markets.

Ivanev wrote:They are doing their work which is good enough and they have better things to do. There is scope for improvement but useless criticism don't help things.

All the big players seem to have no work to do and are busy creating jazzy videos or presentations just to make fanboys happy :) . My understanding is that creating a buzz about your achievements will help you to attract/retain talent and at the same time get big customer. Else believe me 100% FDI in defence will be a serious issue down the years for HAL.
ISRO has been fairly successful in marketing the PSLV with developed countries using its services though its launch telecast are still pathetic :twisted: .
If HAL has great choppers then just increase production, get new buyers and earn foreign exchange. Simple

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Re: LCA News and Discussions, 22-Oct-2013

Postby Cosmo_R » 31 May 2014 16:45

nukavarapu wrote:
Read the article properly, its a speculation. They have not finalized it yet. Its very tough to believe that IAF has been working with Rusky turbo props for so long and an experienced pilot will make such an error. I will believe it once the final findings come out with undeniable proof. Till then all bakwaas !!!


No need to fulminate. Just offering up a data point without comment.

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_23694 » 31 May 2014 17:08

nukavarapu wrote:If HAL is so bad in marketing, then how did they end up selling ALHs to so countries outside India?

I give up on this Sir :) . BTW who were the export customers for ALH and what was the numbers. Long long time back I had read about the unsuccessful attempt to sell ALH to Israel. Failed to sell even to Vietnam which is a good friend of India

nukavarapu wrote:How much marketing did the former USSR do for Mig-21 to make it the most produced and most sold fighter ever?

In which year are we living :-? . I thought 2014 :). No cold war . No Blocs and dedicated customer. Its all about competition Sir.
My understanding is ALH, LCH, LUH and Tejas Mk.2 have good export potential . Please HAL exploit it to the hilt

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Re: LCA News and Discussions, 22-Oct-2013

Postby vsunder » 31 May 2014 20:15

I have a question: Is the In-flight refueling probe on the LCA retractable? It will be an awfully tight fit in that nose cone. Fuel line, retraction mechanism if retractable, probe, radar, parts of the cannon, I would suspect the gun/cannon will be near the centreline as it is a single cannon, CM issues as Rahul M points out.

A poster remarked one should go ahead and grant FOC to the LCA without cannons, BVR and retro-fit. This is an intrinsically bad idea, even historically. First as Rahul M has amply pointed out, that the gun recoil may not pass through the CM and thus may create instabilities in the weapons platform. In addition there are vibration issues as pointed by Shiv. These over time if not taken care of weaken the airframe and of course the FBW has to be modified to account for the recoil not passing through the CM, and thereby achieving a stable platform when the guns operate. This may be a simple fix for one aircraft, but to fix many, may invite another round of breast beating that ADA are morons and did not understand and anticipate these issues and thus have proved to be a burden on the exchequer.

Secondly, historically the F4-Phantom was inducted into the Armed Forces of the US without a cannon. Later in hindsight a cannon was added. The prevailing thought being that missiles would rule the day in future air wars. That doctrine was shown to be wrong in Vietnam. Vietnam showed two things. First, cannons were important, aircraft armed by missiles do not rule the skies and second, close in dogfighting skills are absolutely necessary. Thus the US set up its Topgun school. There is a famous anti-Indian congressman who is a decorated Vietnam vet and was behind bars who was involved in a dogfight that amply illustrated the dangerous idea of sending planes into combat without a working cannon. His name is Randall Duke Cunningham and he set up the Topgun school based on his experiences in 'Nam. Thus flying LCA's without cannons and even more so without BVR capability is flouting the lessons of history. Even the simple expedient of painting the enemy aircraft with radar and a BVR threat, has kept the Pakistanis at bay at Kargil, older veteran forumers will recall this from the heady days on this forum during Ops Safedsagar, you can hear a pilot on Akash Yodha declaiming this fact. The following video amply illustrates why cannons are as important in the setting of today's aerial warfare as they were in World War 1 and for Indra Lal Roy:

Listen to the opening lines " Pilots still need to put lead on target to survive."
The Gun Kills of Vietnam

Duke Cunningham

Again I am confident there are forumers here who may have more insight into these matters than I have and may wish to add pertinent viewpoints or maybe these points have already been elaborated in the past, and for that I am sorry to waste the time of the cognoscenti.

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_26622 » 31 May 2014 22:29

WOW!

I would really like to have every nay sayer for LCA production run to sit and fly a Mig-21 tomorrow. Let's see who chicken sh*ts out. Like I said - easy to nit pick when your ass is not going to be fried Correct!

Regarding HAL not delivering or quality issues -> Remember quality comes with experience building air frames (not bolting things together) and using the machine to begin with. Let's re-evaluate after they complete a 100 airframe order with an aggressive 2 year target. Look at how Chinese got to where they are today. Now let's start the journey and not waste anymore time on our lazy ass*s (tongue wagging is not an exercise).

We have HAL today and no matter how much bad we feel they are, that's what we have got. Even Mahindra was a pile of junk but in 10 years they are turning out world class products (and I can attest to this personally). How do we bring forth this change in HAL , privatization, splitting in to engine, helicopter and airplane divisions and so on are great thoughts. Personally, I agree that we need to slim down this big beast to tame it and get them out of bolting together airframe business. Necessity to stay alive will kick in and they will work harder.

All said, we need to start making 50~100 LCA airframes per year expeditiously. China is showing it's growing fangs in South China sea and it's a matter of a few years at most before they decide to show India its place. Let common sense and judicious risk management prevail here!
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Re: LCA News and Discussions, 22-Oct-2013

Postby Rahul M » 31 May 2014 22:37

raghuk, you need to ignore the whines on the way and provide hungry jingos with scraps of info,
like current state of LUH, LCH and IMRH projects. ;)

vsunder sir, LCA's cannon is mounted under the starboard air intake, so it's not on the centreline.

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Re: LCA News and Discussions, 22-Oct-2013

Postby vsunder » 31 May 2014 23:56

Rahul M thanks for the clarification. Did you know a person called Greenleaf from your madrasah days?
Also have you been following the stuff on transmission eigenvalues? The defence applications are enormous. No wonder the US Air Force is pumping so much money. Funnily the main existence result here is due to me and discovered in an entirely different context 15 years ago. Almost all papers and now there is even a big book by Colton and Cakoni will use that idea. I have heard some lectures where the applications were to Stealth and non-destructive testing. Very nice!!!

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Re: LCA News and Discussions, 22-Oct-2013

Postby Kakarat » 01 Jun 2014 00:06

One More picture from the Weapons trials ( Tarmak007 FB)
Image

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Re: LCA News and Discussions, 22-Oct-2013

Postby shiv » 01 Jun 2014 07:17

I doubt if the LCA wil carry anything more than 150 to 250 rounds of ammunition - enough for about 3-4 seconds of shooting with a Gsh23

What intrigues me about this is that in competitive shooting there is a concept known as "lock time" - which is the lag period between pressing the trigger and the bullet actually leaving the barrel. Since the actual point that the gun is pointing at is always moving relative to the target (unless both gun and target are fixed and totally immobile) the lag time needs to be as short as possible. That means that if a pilot finds that his gunsight is on the bead and presses the trigger - then "bdrrrrp" the rounds have to have left the barrel within microseconds for them to be on target. Not trivial.

That apart -Wiki aunty says the muzzle velocity of Gsh 23 is 700+ m/sec. That means that the bullets will take nearly a second to reach 500 meters. So I am guessing a certain amount of spread of cannon shells is desirable (like spreading shot from a shotgun) so that at least one shell scores a hit despite movement.

A short sharp "press and release" of a trigger lasts about 0.2 sec. That would be just 10-12 shells. Presumably a half to one second burst would put a lot more shells in the area of the target. So I guess it would be necessary for the LCA to be able to fire at least one second bursts. Perhaps one second bursts would do less vibration damage and cause less yaw than longer bursts?

In terms of strafing ground targets - say a truck that represents a 5 x 10 meter target. An aircraft at 900 kmph would be doing 250 meters per second. A one second burst at this speed would put one 23 mm shell per every 4 meters on average. So a truck sized target would at best get about 2 shells. That is enough but the amount of ammunition carried would probably last for just about 3-4 such strafing runs.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Yogi_G » 01 Jun 2014 07:30

shiv wrote:What intrigues me about this is that in competitive shooting there is a concept known as "lock time" - which is the lag period between pressing the trigger and the bullet actually leaving the barrel. Since the actual point that the gun is pointing at is always moving relative to the target (unless both gun and target are fixed and totally immobile) the lag time needs to be as short as possible. That means that if a pilot finds that his gunsight is on the bead and presses the trigger - then "bdrrrrp" the rounds have to have left the barrel within microseconds for them to be on target. Not trivial.


Shiv saar, wont the Fire control computer factor this delay/wind speed/AoA/target velocity etc etc and provide the "shoot" indicator (aural cum visual) to the pilot accordingly? I have seen this in 2-3 fight simulators so wondering if this is indeed a real world thing.

I doubt if the LCA wil carry anything more than 150 to 250 rounds of ammunition - enough for about 3-4 seconds of shooting with a Gsh23


Given that the mk1 will be used more in the originally envisaged role of point defence fighter, the number of rounds is in line with what the mig-21 used to carry.

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Re: LCA News and Discussions, 22-Oct-2013

Postby srin » 01 Jun 2014 10:20

Sorry Shiv-ji, agree with most of the post, except for one (see later below).

The kind of Gatling gun used makes a difference. The Russian gun is gas operated which enables it to respond quicker to trigger press, while the American guns used a different principle which, while slower on the trigger, could fire more rounds in a given time.

Also, while Mig-29 and Sukhois have 30mm guns (Mig-23 has 23 mm I think), the F-18/F-15/F-16 use a 20mm gun. OTOH, the Russian aircraft carry less rounds (<200) while the American aircraft carry a lot more (>500 I think).

Interesting differences in perspective, though I don't know what the philosophy behind it is.

shiv wrote:In terms of strafing ground targets - say a truck that represents a 5 x 10 meter target. An aircraft at 900 kmph would be doing 250 meters per second. A one second burst at this speed would put one 23 mm shell per every 4 meters on average. So a truck sized target would at best get about 2 shells. That is enough but the amount of ammunition carried would probably last for just about 3-4 such strafing runs.


To strafe a ground target using the gun, the aircraft has to point its nose at the target (so it is flying in a down slope) and for the gun to be effective, it needs to get really close to the target (may be couple of kilometers). Given this scenario, I don't think the aircraft would be flying even close to 900 kmph (though i have no idea what speed it should fly).

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Re: LCA News and Discussions, 22-Oct-2013

Postby sarabpal.s » 01 Jun 2014 10:57

Naval LCA NP 01 has gone supersonic in march this yrs quietly as per shiv aroor twitter handle

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Re: LCA News and Discussions, 22-Oct-2013

Postby shiv » 01 Jun 2014 11:06

Yogi_G wrote:
Shiv saar, wont the Fire control computer factor this delay/wind speed/AoA/target velocity etc etc and provide the "shoot" indicator (aural cum visual) to the pilot accordingly? I have seen this in 2-3 fight simulators so wondering if this is indeed a real world thing.

Oh absolutely - but still the "window" of time for shooting is likely to be small depending on range and relative movements of the two aircraft. So a gun that responds instantly to a trigger press would probably be better than one with a lag. I am not sure how much the lag is. Humans have a lag phase in their reaction of about 0.2 sec - so the fire control computer would probably compensate for this to an extent by predicting the point at which the triger needs to be pressed and giving a warning. Don't know for sure.

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Re: LCA News and Discussions, 22-Oct-2013

Postby shiv » 01 Jun 2014 11:17

srin wrote:To strafe a ground target using the gun, the aircraft has to point its nose at the target (so it is flying in a down slope) and for the gun to be effective, it needs to get really close to the target (may be couple of kilometers). Given this scenario, I don't think the aircraft would be flying even close to 900 kmph (though i have no idea what speed it should fly).

In fact 500 knots (926 kmph) is fairly routine speed in level flight. In a dive it will go higher, but I am sure that with the nose pointed at a single target - the latter at least will get a decent spray before the a/c has to pull out of the dive.

I don't think any of these guns have an effective range over 1000 meters. In a dive that 1000 meters will be the hypotenuse of some right angled triangle where the altitude is far less than 1000 meters with the the angle of dive being something less than 45 degrees (maybe 30 degrees?). So the plane will be approaching earth at an insane speed - maybe 150 or 200 kmph from a height of less than 1000 meters (it will take me a fair amount of time to do what is actually a trivial calculation - I am out of touch). Unless he is fully aware of what is happening (or there is a ground proximity warning system) the pilot may have just 4-5 seconds to hit the ground before he pulls out of the dive.

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Re: LCA News and Discussions, 22-Oct-2013

Postby saje » 01 Jun 2014 12:10

shiv wrote:I doubt if the LCA wil carry anything more than 150 to 250 rounds of ammunition - enough for about 3-4 seconds of shooting with a Gsh23


I've been a flight sim addict for the past 13 years and one of my favourite & frequent games is the 'Wings over... series' particulary the game 'Wings over Israel'. This game has some pretty realistic flight models and very light 'gizmotronics'. So based on my experience playing this game, I've found that usually I hardly get enough time or opportunity to put a steady stream of bullets on the bogies because of a variety of factors -- high G manouevres by the boggie, SAMs firing at me, the bogie's wingman trying to shoot my **s off, my wingman screaming his head off, my fuel level going down, the mission window closing etc. So more often than naught I invariably land with enough of my bullet load remaining even after having shot down a few boggies.

For.e.g, just after having read this discussion today, I opened the game and flew a Nesher fighter mission against two Mig-21MFs, shot down both of them and after I switch off the mission, the mission statistics screen shows the gun stats as 104 bullets fired, 3 hit, 2 kills, 2.88% accuracy. I've had similar experience vice versa, flying the Mig-21 and shooting down Nesher/Mirages. And mind you, this is without a gun computer to aid my aiming (this game simulates Israel-Arab aircombat in the 1960s & early 1970s). In the same game while flying F-15s & F-16s with computer aided sights, my accuracy is better. So I guess with a gun computer 150-200 rounds are more than enough for an average aircombat sortie... straffing ground targets? Better left to attack helicopters these days. JMO.


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