Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

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Pratyush
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by Pratyush »

Shekhar Singh wrote:http://ajaishukla.blogspot.com/2019/01/ ... force.html


As per the proposal of HAL, , Weren't they going to produce working prototypes first?

No sense for IAF to put that huge sum on a paper drawing as of now.
Why would you need to have working prototype. What is being done that requires this action. The airframe remains unchanged. The 414 integration is not a huge issue. The big change is the addition of AESA radar.

So why.

Not like the mk2 which is effectively a new design fighter.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by Bala Vignesh »

Even if a prototype is required, they can convert one or two of the LSP’s to this role in a short time. Ideally this should have already happened but the focus on FOC certification may have prevented it.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by Karan M »

>> “Much of the delay is due to changing Tejas specifications. Tejas production was cleared in 2013. But, from that time till today, there have been over 300 changes to the fighter. We need to freeze a single standard for the fighter,” points out Madhavan.

This is exactly what I had constantly referred to, the IAFs tendency to issue piecemeal requests for changes leading to multiple ECR (Engineering Change Requests) which added to constant engineering efforts, while maintaining in public there were no changes as per ASR being the same as before. The dysfunction caused by the IAF joining the program late has had an impact. Anyhow, lessons for the next program hopefully!
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by Philip »

A US publication , Defence News, has rated HAL higher than Dassault for market presence at no.38 while Dassault is ranked at 44!

The GOI should support HAL to the utmost in paying its dues first before we pay Dassault for the 36 Rafales!
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by nam »

I don't think it lesson has been learnt. The fact that there is only 16 FOC on order and a "promise" of 83 for a version which is not there yet, tells us frankly is that IAF is playing merry go around.

Don't understand why FOC version production should not be continued until MK1A comes online.

As i mentioned earlier, the fault is with MoD, who is watching this nonsense, instead on laying down a red line. I can guess the MK1A version excuse came about when Parikkar refused more Rafale and floated a SE RFI in return for IAF buy in for LCA.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by Dileep »

Those who watched the AI19 webinar on the Navy version would figure out how the correction mechanism for random changes work :)

The flight control is a control loop. If the aircraft tend to depart from the set value of Y/P/R, the control loop will compensate by moving whatever control surface required to bring it back to the set values. The beauty of the system is that the loop doesn't need to know the cross link between Yaw and Roll. It will automatically correct both.

It is not just weapon release. The fighter is expected to be hit by enemy fire too, right? The FCS will have to compensate to the maximum extent possible for change in aerodynamics due to enemy damage. We do not simply give up and die (like the Perry Mason perps) at the first shrapnel hit!!

Being said that... this point is grossly ignored by the folk at ADA. For them, it is unbelievable that their 'chocolate baby' will have to suffer as much as a scratch. Lucky that the FCS doesn't look at the cause of change in aerodynamics.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by SriKumar »

Dileep wrote:Those who watched the AI19 webinar on the Navy version would figure out how the correction mechanism for random changes work :).

It is not just weapon release. The fighter is expected to be hit by enemy fire too, right? The FCS will have to compensate to the maximum extent possible for change in aerodynamics due to enemy damage. .
great, nice point. The damage here can be random with no prior idea of how it will look, and would be more challenging to design for than any release of ordnance which are at known locations and known weight/drag profile. This Probably would have been the most challenging scenario for FCS design. E.g. What if multiple sensors were hit and FCS cannot even get the aerodynamics readings.( actual/nonmarginal damage of airframe is another can of worms). For an inherently unstable craft this is critical for any degree of survivability.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by mody »

Pratyush wrote:
Shekhar Singh wrote:http://ajaishukla.blogspot.com/2019/01/ ... force.html


As per the proposal of HAL, , Weren't they going to produce working prototypes first?

No sense for IAF to put that huge sum on a paper drawing as of now.
Why would you need to have working prototype. What is being done that requires this action. The airframe remains unchanged. The 414 integration is not a huge issue. The big change is the addition of AESA radar.

So why.

Not like the mk2 which is effectively a new design fighter.
There is still confusion about the scope of work for MK1A and MK2.
Changing the engine to GE F414 is not part of MK1A. It is for MK2 only.
MK1A has only the following major requirements:
1). Radar change to AESA Elta 2052.
2). Addition of an external EW pod. Seems it will be Israeli pod. Will be mounted mostly using a twin rack system on the mid wing pylon.
3). Internal re-organization of LRUs for ease of maintenance. Some LRUs might be indegenized, as this is a continuous endeavour. Fighting obsolescence is also a factor and some LRUs will be updated on this count.
4). Integration of better BVR missile to take advantage of the higher range radar. Most likely will be Derby-ER. If problems with Python V can be sorted out, the same will be integrated as well.
5). Software defined radio SDR, will also likely be a requirement. Some reports suggested that IAF was asking for it as part of FOC. So I guess it will be included as a requirement for MK1A.
6). Any possible weight reduction. HAL in its initial presentation for MK1A had claimed that some weight reduction is possible. Claims at the time quoted unrealistic figures like 800Kgs. However, maybe a reduction in the range of 150-300Kgs might be possible. Some of the dead ballasts used in the MK1 are likely to be got rid of.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by Prem Kumar »

nam wrote:I don't think it lesson has been learnt. The fact that there is only 16 FOC on order and a "promise" of 83 for a version which is not there yet, tells us frankly is that IAF is playing merry go around.

Don't understand why FOC version production should not be continued until MK1A comes online.

As i mentioned earlier, the fault is with MoD, who is watching this nonsense, instead on laying down a red line. I can guess the MK1A version excuse came about when Parikkar refused more Rafale and floated a SE RFI in return for IAF buy in for LCA.
+100. We were all so disheartened by LCA's prospects at one point that a promise of 83 MK1A came as a relief. But objectively speaking, the FOC order volume is pathetic and betrays a complete lack of understanding (or apathy) towards economies of scale or supporting our MIC. The IAF just comes across as a recalcitrant child forced to eat brinjals by his mom.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by Indranil »

Haridas wrote:
Kakarat wrote: Its not new, It has been there for at least a couple of years now
Are these the new low drag pylons?
No. But using the tandem arrangement gives significant form drag reduction. One thing that I am keenly looking forward to is the pinched 1300 ltr DFTs. That will reduce drag. But, more importantly, it reduces the interference between tank and the ordinance leading to better weapons delivery accuracy. But, even without that, LCA had the best A2G scores at Gaganshakti. I am hearing that the supersonic tanks are also getting ready. But the utility of supersonic tanks is very limited.

I keep asking my friends in ADA why they haven’t gone for such a low hanging fruit as the low drag pylons. I get the feeling that it was a case of priorities. FOC items were top of the list.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by vera_k »

nam wrote:Don't understand why FOC version production should not be continued until MK1A comes online.

As i mentioned earlier, the fault is with MoD, who is watching this nonsense, instead on laying down a red line.
Since the missile force and nukes are being built, MoD may be playing along with minimal funding. Kind of like the PRC strategy 30 years back of funding research but not constructing a lot of modern types.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by ramana »

Mody regarding 4), the Python has too many fins and there is airflow interference at the pylon with Tejas wing.
Most likely Python won't be fitted. ASRAAM seems to be the choice. Let's see.

I wish we had folks who could do system studies of a short range missile with Python like seeker.

Or locate the Python at different location.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by John »

Contract for 83 should be signed soon.

https://www.thehindu.com/news/national/ ... 980989.ece

HAL has also stated that with anticipated collections up to March, the cash position is expected to improve and in terms of future orders, final contracts for 83 LCA Mk1A and 15 LCH are in advanced stages.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by Neshant »

John wrote:Contract for 83 should be signed soon.
What have they been doing all this while.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by dinesha »

Indranil
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by Indranil »

Everything is fine. But why not specify these requirements on time? The IAF is clearly in the loop for all the testing feom day 1.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by pralay »

dinesha wrote:Now, IAF wants new canopy for LCA
https://timesofindia.indiatimes.com/ind ... 550885.cms
Article does not say how much weight it will add, can experts here weigh in ?
Also will this change apply only to the front wind-shild or the whole canopy ?
Last edited by pralay on 16 Jan 2019 15:50, edited 1 time in total.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by nam »

I am now fully convinced that IAF will delay LCA induction until there is movement on MMRCA 2. Called me CT, MK1A was an excuse to give time to MMRCA/Rafale.

IAF is not forth coming with MK1A order and making changes for delaying FOC production of what is after all 16 jets. There is no reason canopy cannot be considered for MK1A.

The only silver lining is that HAL does not have any other orders, hence will lobby for LCA.

MoD needs to draw a line.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by nam »

pralay wrote:
dinesha wrote:Now, IAF wants new canopy for LCA
https://timesofindia.indiatimes.com/ind ... 550885.cms
Article does not say how much weight it will add, can experts here weigh in ?
More than the weight, it will require re-certification as it is a hardware/structural change. Along with it, production drawing has to change and probably HAL has to look for another provider.

Fundamentally it will delay production.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by ArjunPandit »

^^have patience, IMO these are all unnecessary noises before the election. These things will come in due time, Dilip & Indranil were not that pessimistic. I would trust them more than the DDM
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by UlanBatori »

What's wrong with IAF wanting a new roof? That is the whole beauty of having ur own design for the plane: you can keep improving it, like George Washington's Axe:
It's the very same axe with which George cut down the cherry tree, but the handle has been replaced 17 times and the blade 67 times, and now incorporates this neat laser chain saw plus kick-back warning heads-up display.
I take it as a great sign. Also that Indian birds are now much better-fed (40gm vs. 20gm).
Now if that were a Rafale with Bofors cannons, it would take 20 years, 3 governments, 5 Inquiry Commissions, and enough hot air to melt down Kanchanjunga before they could change the canopy on it.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by Singha »

pralay wrote:
dinesha wrote:Now, IAF wants new canopy for LCA
https://timesofindia.indiatimes.com/ind ... 550885.cms
Article does not say how much weight it will add, can experts here weigh in ?
Also will this change apply only to the front wind-shild or the whole canopy ?
I am hoping its just the front part. the back part which opens also has a explosive liner inside for ejection. change that is more involved and would involve ejection test again using rocket sled or whatever means. good thing for once we have a old fashioned canopy rather than the huge bubble canopies that completely open.

the more mystifying is the refueling probe light. surely this is a failure of requirements capture and review by first IAF and then HAL.

so is there any other fighter or heavy in IAF that does night refueling at present ? any pics or videos ?
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by Singha »

based on this it will be the whole canopy. and the mighty F-solah has 0.67 inch thick which maps to *cough cough* 17mm .... same as the Tejas

https://aviation.stackexchange.com/ques ... ss-shields

hope they dont ask for supersonic impact protection with a gigantic vulture tooling around or those fat uber geese that do LR flights over the himalaya at 30,000 feet.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by nam »

For night fueling, does the tanker have probe lights to do night fueling? As far I remember, CSIR recently created a lights for night fueling for the tanker probe.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by mody »

ramana wrote:Mody regarding 4), the Python has too many fins and there is airflow interference at the pylon with Tejas wing.
Most likely Python won't be fitted. ASRAAM seems to be the choice. Let's see.

I wish we had folks who could do system studies of a short range missile with Python like seeker.

Or locate the Python at different location.
I think we are using the ASRAM with the Jaguars. Maybe the IRIS-T and Aim-9X can also be considered. I guess the sidewinder would be the cheapest. As many have suggested, maybe DRDO can take bup a project to develop our own WVR missile. The seeker seems to be within our capabilities. Though a wide angle of vision for high off bore sight would need some work. A thrust vectoring solid rocket motor, capable of high G manvoures is another challenge. Avoiding flares and decoys is the other aspect.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by yensoy »

UlanBatori wrote:Now if that were a Rafale with Bofors cannons, it would take 20 years, 3 governments, 5 Inquiry Commissions, and enough hot air to melt down Kanchanjunga before they could change the canopy on it.
No that's not the way it will work out. IAF will ask for a new canopy. Dassault will say "can't do". Then IAF will say, oh well we will manage.

LCA being ghar ki murgi will get mistreated like one.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by chola »

Singha wrote:based on this it will be the whole canopy. and the mighty F-solah has 0.67 inch thick which maps to *cough cough* 17mm .... same as the Tejas

https://aviation.stackexchange.com/ques ... ss-shields

hope they dont ask for supersonic impact protection with a gigantic vulture tooling around or those fat uber geese that do LR flights over the himalaya at 30,000 feet.
Singhaji, you are being facetious. Being familiar with your wide knowledge base, you would have known that the highest flying bird in the Himalayas is the Bar Headed Goose and that vultures feed only on carrion.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by Dileep »

The primary problem is ADA will not (rather can not) say NO, unless a really convincing technical impossibility can be found. I mean impossibility not difficulty. The latter doesn't fly with the 'demanding' and 'discerning' kashtamar onlee. Push back will only result in escalation to the levels that have no clue on the difficulty, and order to "get it done".

I have a theory. There are serious obsolescence issues on some parts, and the teams were scrambling to find solutions. Maybe there is going to be delay to get everything together for SP2X anyway, so some more modifications are being sneaked in utilizing the delay.

I don't think even IAF (who already developed a sizeable group of fanboys for the plane) will cause deliberate delays at this stage.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by VinodTK »

ArjunPandit wrote:^^have patience, IMO these are all unnecessary noises before the election. These things will come in due time, Dilip & Indranil were not that pessimistic. I would trust them more than the DDM
After the elections if there is a change in Govt., priorities will shift focus might not be on defense and make in India, IAF will have to reactivate their crown jewels (de-commissioned Migs).
I would not be shocked if the delivery of Rafale is stalled because of some kind of probe that might be ordered by the new Govt. to prove their point.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by Singha »

A member who wishes to remain anon sent me

BTW windshields of Commerical airplanes are 12 mm outer and 4 mm inner. With a 4 or 6 mm airgap.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by John »

Neshant wrote:
John wrote:Contract for 83 should be signed soon.
What have they been doing all this while.
The usual price negotiations while writing blank checks for Russian imports..
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by ArjunPandit »

Singha wrote: the more mystifying is the refueling probe light. surely this is a failure of requirements capture and review by first IAF and then HAL.

so is there any other fighter or heavy in IAF that does night refueling at present ? any pics or videos ?
Saw tweets from vijender thakur, an ex jaguar pilot, he mentioned fuel/flight profiles can only be figured out only in sqdn service after fine tuning mission profiles etc, something of that sort (dont have precise verbiage). IAF is experimenting a lot with this. I expect it to be the light MKI of IAF. My main point being IAF fully interested in it and suggesting improvements.

Now imagine the ego flattening of a proud russian designer, a country that has been designing planes before there India existed (according to him), and SDREs come and say to his your plane (Read Pakfa) has XYZ deficiences, let's redesign the plane together.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by ArjunPandit »

VinodTK wrote:I would not be shocked if the delivery of Rafale is stalled because of some kind of probe that might be ordered by the new Govt. to prove their point.
what this govt has started, it will be very difficult to undo, i wont be surprised if IAF itself says to the new regime that give us more budget for tejas
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by ArjunPandit »

Dileep wrote:There are serious obsolescence issues on some parts
Dileep sir, may i request you to educate this nanha in this area. High level parts like radar, engine, FBW, missiles, etc dont seem obsolete. But then I dont know anything under the hood.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by ashishvikas »

Is Tejas going to fly plast on Republic day this time as well ?
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by Karan M »

ArjunPandit wrote:
Dileep wrote:There are serious obsolescence issues on some parts
Dileep sir, may i request you to educate this nanha in this area. High level parts like radar, engine, FBW, missiles, etc dont seem obsolete. But then I dont know anything under the hood.
There are a gazillion processors and memory modules in all sorts of avionics. Most have been replaced already. But even smaller stuff like a get you home panel will have replaceable LRUs that need to be kept up to date.
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by suryag »

One of the items when I worked on(before the first flight) was powerpc based control card to combine data from different sources, not sure if they changed it in 2006-7
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by dkhare »

dinesha wrote:Now, IAF wants new canopy for LCA
https://timesofindia.indiatimes.com/ind ... 550885.cms
Based on the article, ADA and HAL seem to have taken the request in their stride and have already made a lot of progress. Agree with Indranil, this should have been identified way before - unfortunately it seems to have been missed by the IAF.

The theory that Dileep put forward about "serious obsolescence issues on some parts" is more concerning.

This is our bird - modifications and upgrades will be requested. MoD should manage them in blocks minimizing additional delays.

I wonder if the white paper and drawings we had seen for refining the shape of the canopy will be incorporated into this request. There were some gains in drag reduction. Or was that for LCA Navy?
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by Singha »



fighter canopy vs car windshield - tested with a huge tyre @ 225kmph
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Re: Tejas Mk.1 & Mk.1A News & Discussions: 09 February 2018

Post by ramana »

Electronic piece parts have ten year obsolescence timeline. Means you cant go to market and buy them.
Hence the need to have quantity buys or what is called life of type buy.
Obsolesent parts mean new parts need to be qualified and boxes built using them have to go thru original qual tests.
Very time consuming and thus costly.

With ADA in never-ending saga of completing development, and IAF not putting foot down, MoD watching parts become obsolete by end of production run.
Hazards of not making a plane in quantity for decades.
And not learning MoD system.
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