ADA Tejas (LCA) News and Discussions

[Rahul Singh]

Yes as explained, the weight incerase of using bombs and the limited fuel capacity of the centerline station makes that unavoidable, which ADA confirms that too:

http://i.imgur.com/GEW98nW.jpg

If you would inform yourself and not only conclude things, you would have know that.

HAHAHAHAHA

In that picture from ADA, kindly locate me the factor-of-range in stated load configuration?

Did it (ever) occur to you that what's depicted in that pic is an ideal configuration which in other words means optimum load at the farthest distance or optimum load for max endurance?

Let me again repeat this. A distance between Pathankot and Lahore is 145 and between Srinagar and Skardu is 154. And Tejas has a range of +500kms(internal fuel only) with an optimum combat load.

Now, do you really think to strike at 1/3rd of it's stated range Tejas would be required to double its fuel load? Do you even understand what at all drop tanks are required for?

Let me repeat it but your words. Inform yourself and before trying to conclude, improve your understanding of things you read out of brochures.

Depends on the weight and size limitations of the hardpoint. The mid wingstation for example might get a twin launcher for 500lb LGBs, instead of the single 1000lb. But that still doesn't give any hardpoint for BVR missiles.

If the mid-board station can get tandem bomb racks. The outer board is already getting twin rack for carrying SPJ in addition to a WVRAAM (which will be repeated on other side also, obviously for balancing the weight thereby increasing no. of WVRAAM carrier to 3x). Then why the heck mid wing stations can't be equipped with a type of twin rail launcher not in side by side configuration but in configuration as seen in the pic(just below) keeping in mind space limitations for BVRAAM carriage?

Nope, factually! You are the one that is using imaginary specs and loads out of the lack of proper infos and understanding.

Don't be delusional. Don't mistake yourself for me.

With regard to MK-2 i have already posted a video in which an Air Marshal(retd) said ".......MK-2 is in the vicinity of Mirage-2000......".That after i had put estimated capability MK-2 vis-i-vis Mirage-2000 using figures put in official brochures by ADA.

Basically explained above... The mid wing station would be able to carry the twin launcher and 2 x SAAW, while it won't be able to carry a quad launcher and 4 of them at that station. That would only be possible at the inner wing stations, maybe on the centerline, but that needs to be seen (size limitations).

So, now you are not crying for official specs and have accepted the possibility of MERs being carried on MK-2 which in all likelihood will be because Tejas Mk-2 is only getting bigger with larger wingspan.

Now what about your assertions that Tejas does not have / won't have enough hardpoints and range(since you believe 2x drop tanks are must irrespective of range requirement) for strike missions? Do i need to mention that SAAW weights only 120kgs(against a +500 pounds LGBs) with stand-of-range of 100 km(against 12-20 kms).

In case you are wondering about the context. Here is what you had said.

Your words below(in red):

"That still doesn't deal with the lack of hardpoints, but at least would make Tejas compliant to a decade old ASR and useful enough for the interceptor role it was meant for".

http://defenceforumindia.com/forum/goto/post?id=1409651#post-1409651

Lol, a dumb bomb have no guidance or navigation kit's, unlike smart bombs like LGBs or satellite guided bombs like JDAM.
Also one of the advantages of smart bombs is, that you can launch them further away from the target, to not be exposed to ground threats. Dumb bombs on the other side, are launched directly overy the target.
But to be smart, you need guidance kits, with fins that requires larger space => lower numbers of bombs.

Where did i say Dumb bombs have guidance systems?

Let me rephrase my words. Every LGB like a Paveway or Griffin type bomb is a mix of a dumb bomb/iron bomb/gravity bombs and a guidance kit. In these types of bombs, a tail unit as well as a nose unit are attached to tail and head section of an iron bomb thereby converting it into a PGM. In this case, the overall length of the bomb almost doubles.

In case of JADM type bombs, an iron bomb is bolted with only a tail section and some midbody slates. Here in this case, the overall length of bomb does not increase much over what are loosely mentioned as Dumb Bombs.

A dumb bomb is a bomb with a static tail unit quite similar in length to tail units of JADM kits. Tail units of JADM kits have moving ailerons unlike that of dumb bombs.

Just to keep the context in focus. Here is what you had said

Your words(below):

But even the Jag today, don't use that kind of configuration anymore, because guided bombs are the standard, which require more space than dumb bombs.

http://defenceforumindia.com/forum/goto/post?id=141#post-141

Omnirole is a PR term used by Dassault only =>

https://www.dassault-aviation.com/en/defense/rafale/omnirole-by-design/

Yeah, i know about Rafale.

But don't forget to define SU-30MKI as per your "Lahori logic' stated few posts earlier. Is it multi-role or swing role?

link what you had said earlier.

http://defenceforumindia.com/forum/goto/post?id=1411341#post-1411341

The point is always the same, a single fighter can be used in various roles, without the need of specific customizations or versions, as it was the case for older 2nd and 3rd gen single role fighters. The only difference for swing role, is as explained the instant change of roles and that's where light class fighters, with limited load capabilities, are had capped by design.

Let me rephrase my words again. The ability of a fighter to quickly adapt to A2A to A2G in single sortie makes it a swing role fighter. This is provided by the inherent design feature which in the present case is an unstable airframe with a properly developed FCS for making a single design more manoeuvrable as well as highly stable at the same time for A2A and A2G applications respectively.

Here it doesn't really matter if a fighter drops and fires 2xLGBs and 2x ARMs + 2x AAMs. Or 4xLGBs and 4xARMs + 6x AAMs. For distinguishing between these, load dependent terminologies are used namely Light, Medium and Heavy.

That's the difference between informing yourself first, instead of just getting into conclusions based on an opinion!

Use a mirror. Its better spoken with it.

 

[Rahul Singh]

IAF will not send Tejas or any plane without an external SPJ

800 L tanks are also good enough

IFR is Impractical for all planes

Tankers are limited in number so they will get prioritised
in a conflict

Tankers and Drop tanks are required if there is a need to extend range/endurance. Their requirements are defined by the type of mission one is required to carry out.

In case of the western front, Tejas will be mostly employed for tasks within its range of 500 km. In case it is given a role beyond that --which will be like striking targets closer to Durand line-- then there will be requirements for extending its endurance/range. In that case drop, tanks and Tankers will be used.

During the war, a tanker acts like a mobile fuel station loitering in an area frequented by friendly fighters. It will refuel whosoever is in need as per mission requirements.

Said that i fail to understand few people who say force multipliers like Tankers will be kept first for SU-30MKIs and only latter for Tejas type (some even say Tejas won't have it at all). Because the role of force multipliers are to bring about the capability of lacking fighter to that of best in concerned respects without changing it.

Which brings me to question why would a Su-30 MKI require the support of a tanker more than Tejas when MKI's range and endurance (on internal fuel alone) is 4 to 5 times of Tejas?

Same goes for the statements that IAF won't free any AWACS for Tejas and keep it for MKIs. Why would MKI require an AWACS with 400 KM range when its onboard BARS has the same range? A logical question that arises, why would not IAF force multiply capabilities of Tejas which have +150 Km MMR with an AWACS with 400KM range working in net contric mode?

 

[Rahul Singh]

I am damn sure that HAL/ADA has no plans for that at the moment.

Weight reduction studies have already been carried out. Mk-1A will see a reduction in empty weight by 200-400 kgs. It was long confirmed by LCA-Tejas FB admin

 

[Rahul Singh]

1.That "limited" fuel capacity is more than enough to cover all prime targets in western sectors & many battle field targets in himalayas.

This is where all the comments regarding shorter legs of Tejas meet their demise.

500Km range with Tanker support is more than enough to cover primary areas of interests on the western front and around TAR.

 

[torque456]

I am also 100 per cent sure of further orders of not just the LCA Mk.1A but at least 200 of the Mk.2. -Dr. Christopher


You guys need to realise mk1a will have a much longer production run than the current 83 ordered. I predict at least 2 squadrons.

 

[Rahul Singh]

TEJAS - MK2 TO FLAY BY 2022 AND IAF GIVEN IN WRITING FOR 201 TEJAS - MK2 BIRDS

DR. CHRISTOPHER

http://indianexpress.com/article/in...etter-than-pakistans-says-drdo-chief-5083268/

India’s AWACS is low-cost, better than Pakistan’s, says DRDO chief
DRDO chief Dr S Christopher said the indigenous AEW&C built by DRDO using modified Brazilian Embraer jets is cost effective and better than the Swedish systems owned by Pakistan.

The indigenous airborne early warning and control system (AEW&C) built by Defence Research and Development Organisation using modified Brazilian Embraer jets is cost effective and better than the Swedish systems owned by Pakistan, said DRDO chairman Dr S Christopher at an event in Gujarat University on Thursday.

Giving an insight into various modern technologies being developed for the military, Christopher, delivering the first i-talk organised by Gujarat Innovation Society (GIS), spoke about how DRDO’s AEW&C platform, christened “Netra”, was close to his heart since he was involved in it right from inception. “In 1985, we thought we should make an AWACS (airborne warning and control system) because at that time the US had brought in their own system,” Christopher said while narrating how the DRDO faced teething problems in the project, which also involved a crash.

The DRDO chief said they had gone for a simpler and smaller platform by using the Brazilian Embraer-145 jets when the project was restarted. “It started with a simpler and smaller platform that is the Embraer,” Christopher said, adding how the five-hour endurance of the system was expanded by adding a complex air-to-air refueling facility.

Claiming that the DRDO’s AWACS was cheaper than its Pakistani counterpart, Christopher said except for the aircraft, the electronics was indigenously made. “Except for the aircraft, all the electronics is ours. So when you compare the cost, it is less than what Pakistanis are having; the Swedish system. In addition to that, their aircraft itself is not as good as ours. It is because our is a jet and that is a turboprop,” the DRDO chief said. Pakistan has Saab 2000 Erieye AEW&C from Sweden.

Tejas Mark-II to fly by 2022

Speaking of Light Combat Aircraft (LCA) Tejas, Christopher said HAL had already got an order to manufacture 123 LCAs. “In addition to that, the air force has given in writing another 201 aircraft, which is the next version, that we call as Mark-II. We are working on it and by 2022 it will be flying,” he said.

If this new is true. Then Indian aviation just got revolutonised. This development is nothing short of that.

There will be heavy investments in R&D and infrastructure for sub-systems manufacturing for Tejas by the private sector for sure.

 

[Bhoot Pishach]

There you go : And now this is from Modi Sarkar - Firm Commitment for Tejas-MK2

Jai Ho Sitharamanji

https://www.livefistdefence.com/201...g-push-from-modi-govt-all-eyes-on-action.html

LCA Tejas Fighter Gets Big Push From Modi Govt, All Eyes On Action
Shiv Aroor Mar 03 2018 5 48 pm

In what is being seen as a timely and hard show of support to India’sLCA Tejas light fighter program, Defence Minister Nirmala Sitharaman today said, “We are looking forward to theLCA Mk.2coming at the earliest. We have made provisions for the program.”

The LCA Mk.2,an improved and more powerful version of the current LCA Tejas, is expected to be ready to fly in three years. With an array of improvements (including in maintainability), better sensors, weapons and engineering changes, it will also be powered by the more powerful GE F414 engine, allowing it a greater operational envelope for more missions. Unlike the LCA Navy Mk.2 which thegovernment decided in 2016 to scrap, the Defence Minister’s word today on the LCA Air Force Mk.2 program comes as a major confidence boost.

The minister’s comments in Delhi today also come at a time when the MoD has justdecided to abort a questto buildeither F-16s or Gripensin India as part of a single-engine fighter production program. The collapse of that effort is being seen as a significant opportunity to accelerate the Tejas program.

Minister Sitharaman however expressed concern over Hindustan Aeronautics Ltd’s current rate of LCA Tejas production, saying that production rates needed to be significantly ramped up for the program to be viable and meet IAF requirements. HAL has struggled with production rates for years, but has pledged to accelerate the speed at which it can churn out the light fighters.

“For instance, if the production rate is six per year, we cant wait six years for 36 aircraft,” she said, adding, “We are putting our full energies into the Tejas program.”

The Indian Air Force, which began inducting the Tejas into squadron service last year, currently operates only a handful of jets. Its current orders total 123 aircraft, which includes 20 in intial operational clearance (IOC) configuration, 20 in final operational clearance (FOC) configuration and 83 in an interim Mk.1A configuration, the full contours of which werefirst reported in detail by Livefist here.

Speaking exclusively toLivefiston the LCA Tejas program, Defence Research & Development Organisation (DRDO) chief Dr. S. Christopher has welcomed the Defence Minister’s words.

“I am absolutely confident that the LCA Tejas Mk.2 will meet all requirements in a timely manner. I am also 100 per cent sure of further orders of not just the LCA Mk.1A but at least 200 of the Mk.2. Both of these aircraft will have tremendous export potential,” Christopher said.

Dr Christopher took a sortie in an LCA Tejas in January with IAF test pilot Air Vice Marshal A.P. Singh in the north east.

“The aircraft has matured wonderfully, to the full credit of our teams of engineers and scientists,” Christopher said. “It is a moment of great pride for us, but also a priority to see that the rest of the Tejas journey is very smooth.”

 

[Madooxno7]

How many prototypes we have ? Of Tejas mk2?

 

[Kharavela]

Vishnu Som of UndyTV has reported #ModiSarkaar 's firm support for #Tejas:

https://www.ndtv.com/india-news/gov...and-f-16-unclear-1819238?pfrom=home-topscroll

That smumbag reported HAL's capacity as 6 Tejas per year.

Work hard in silence, let your success be your noise. - Frank Ocean

 

[Kharavela]

Even the center pylon of tejas can be configured to carry multiple LGBs

SO we will have

1.Any number of LGBs on center line pylons,(limited by pylon weight )

2. Two fuel tanks on inner pylons,

3.four BVR missiles on mid wing pylons,(quad rack will be further improvement upon this,)

4. Two WVR missiles on outer wing pylon.

With a decent range to cover around 400 to 500 Km radius in hi-l0-hi mode.

The fuel fraction calculations in this config is still decent for india's primary theater of war, Pakistani airspcae & Himalayas.

What matters is , even with this config tejas will still have lower wing loading than any other fighter in service in PLAf or PAF.

it means

1.tejas can fly better,

2.will hv lower RCS, meaning better survivability,

3.Can take off from shorter himalayan runways in high altitude than any chinese or pak fighter,

4. Will hv world class HMDS enabled high off bore WVR missiles for close combat,

5. Will hv air to air refueling extending its range & loiter time,

6. With hot refuelling can go in for air policing at far shorter turnaround time,

7. Has best in class engine replacement time in IAF,

8.Will hv DRFM based ASEA Ew suit fr self protection,

All at half the cost of any imported fighter.

After a long time, saw your post in Tejas discussion. Welcome back, Saar.

Work hard in silence, let your success be your noise. - Frank Ocean

 

[Sancho]

The outer board is already getting twin rack for carrying SPJ in addition to a WVRAAM (which will be repeated on other side also, obviously for balancing the weight thereby increasing no. of WVRAAM carrier to 3x).

ADA proved you wrong on the fuel tanks needed for strike loads and here once again they prove you to be wrong:

http://i64.tinypic.com/1rt3e0.jpg

Their "proposal" is to remain with 2 x missiles max and even that is not an approved solution so far, since we reportedly have problems with the integration of Python V and we don't know which SPJ will be selected with what weight...

Then why the heck mid wing stations can't be equipped with a type of twin rail launcher

Who says you can't? But it doesn't solve the problem! You still have only the mid wing station to carry either missiles or bombs, so in strike configs, you can carry 2 x 250 to 500lb bombs, but still have no hardpoints for missiles.

In CAP the addition of a twin missile launcher adds more weight and drag, to a fighter that already suffers from overweight and lack of aerodynamic performance.

That's why the only solution as explained ealier remains, to either add CFTs and free the inner wing stations from fuel tanks, for the use of weapons, or add additional hardpoints, which however requires a re-design of the wings or gear bay / centerline station, by the lack of space.

Don't be delusional. Don't mistake yourself for me.

Lol of course not! I don't claim things that I didn't looked up first, to get a basic understanding. :biggrin2:

In case of JADM type bombs, an iron bomb is bolted with only a tail section and some midbody slates. Here in this case, the overall length of bomb does not increase much over what are loosely mentioned as Dumb Bombs.

And again, no informing => lack of understanding => claiming baseless things...

MK84 dumb bomb:
Weight 2039 lb (925 kg)
Length 129 in (3280 mm)


GBU 31 (MK84 dumb bomb + JDAM kit):
Length: (JDAM and warhead) GBU-31 (v) 2/B: 152.7 inches (387.9 centimeters); GBU-31 (v) 4/B: 148.6 inches (377.4 centimeters)
Weight: (JDAM and warhead) GBU-31 (v) 2/B: 2,036 pounds (925.4 kilograms); GBU-31 (v) 4/B: 2,115 pounds (961.4 kilograms);
http://www.navy.mil/navydata/fact_display.asp?cid=2100&tid=400&ct=2

So no matter if you take LGB or sat guidance kits, to convert dumb bombs into smart bombs, the size will increase. That's why your old wind tunnel model and Jag dumb bomb loads have no meaning for LCA or modern warfare.

Yeah, i know about Rafale.

Yes now that I explained it to you and by providing you the link to Dassault. Your welcome.

The ability of a fighter to quickly adapt to A2A to A2G in single sortie makes it a swing role fighter. This is provided by the inherent design feature which in the present case is an unstable airframe with a properly developed FCS

Wrong, since the FCS doesn't limit the load capability of the fighter, but to switch from 1 role to another, the key is to be able to carry the necessary loads at the same time.

Multi role example:
An LCA is sent for a strike mission and as shown by ADA mission configs, can't carry BVR missiles, so it has to return to base, re-arm for CAP and refuel to switch roles.

Swing role example:
An MKI on the other hand, can do the same strike, remains loaded with at least 2 x BVR + 2 x WVR missiles and only needs IFR to switch to CAP in the same sortie!

 

[patriots]

How many prototypes we have ? Of Tejas mk2?

it's in design phase...it will be slightly longer than Tejas mk1....with some extra features like aesa radar ..jammer ..then more endurance. .etc ..

 

[patriots]

here is something to know about spj .... don't know which spj Tejas will use. but this is from a Israel company....

ELL-8212/22
ELL-8212/22 - Self-Protection Jamming Pod

Main Objectives

*Enhance survivability of fighters and other military aircraft by suppressing multiple threats in dense radar-guided weapon systems environment.

*Protect the aircraft against all types of traditional and modern Air-to-Air & Surface-to-Air threats.

Main Advantages
*Cutting-edge Exciter and Receiver.

*Lightweight, low-drag pod configuration.

*Suitable for aircraft of any size.

*Hundreds of ELTA's Self-Protection Jamming Pods are deployed worldwide. Operational on-board F-16, F-15, F-111, F-4, F-5, A-4, Jaguar, and Eastern fighters.

*Easily integrated with aircraft avionics via reduced dimensions and electrical and mechanical interface flexibility.

*Using PC-based equipment and user-friendly human machine interface, threats and jamming techniques may be easily updated or added.

*Flight line re-programmable.

"Incorporates modern design architecture and advanced technologies, based on ELTA's field proven experience of more than 30 years in the design and manufacturing
http://www.iai.co.il/2013/34486-26545-en/Groups_ELTA_EltaNumber_Products-ELL.aspx
Bhai log do we have our own spj pod. .in development..or we are going to use. this one.....

 

[patriots]

a old report but something to know about mk1a. .. features.....

https://www.livefistdefence.com/2016/06/revealed-the-lca-tejas-that-the-iaf-has-chosen.html

.... .........................................................................

 

[V_Force]

There you go : And now this is from Modi Sarkar - Firm Commitment for Tejas-MK2

Jai Ho Sitharamanji

https://www.livefistdefence.com/201...g-push-from-modi-govt-all-eyes-on-action.html

LCA Tejas Fighter Gets Big Push From Modi Govt, All Eyes On Action
Shiv Aroor Mar 03 2018 5 48 pm

In what is being seen as a timely and hard show of support to India’sLCA Tejas light fighter program, Defence Minister Nirmala Sitharaman today said, “We are looking forward to theLCA Mk.2coming at the earliest. We have made provisions for the program.”

The LCA Mk.2,an improved and more powerful version of the current LCA Tejas, is expected to be ready to fly in three years. With an array of improvements (including in maintainability), better sensors, weapons and engineering changes, it will also be powered by the more powerful GE F414 engine, allowing it a greater operational envelope for more missions. Unlike the LCA Navy Mk.2 which thegovernment decided in 2016 to scrap, the Defence Minister’s word today on the LCA Air Force Mk.2 program comes as a major confidence boost.

The minister’s comments in Delhi today also come at a time when the MoD has justdecided to abort a questto buildeither F-16s or Gripensin India as part of a single-engine fighter production program. The collapse of that effort is being seen as a significant opportunity to accelerate the Tejas program.

Minister Sitharaman however expressed concern over Hindustan Aeronautics Ltd’s current rate of LCA Tejas production, saying that production rates needed to be significantly ramped up for the program to be viable and meet IAF requirements. HAL has struggled with production rates for years, but has pledged to accelerate the speed at which it can churn out the light fighters.

“For instance, if the production rate is six per year, we cant wait six years for 36 aircraft,” she said, adding, “We are putting our full energies into the Tejas program.”

The Indian Air Force, which began inducting the Tejas into squadron service last year, currently operates only a handful of jets. Its current orders total 123 aircraft, which includes 20 in intial operational clearance (IOC) configuration, 20 in final operational clearance (FOC) configuration and 83 in an interim Mk.1A configuration, the full contours of which werefirst reported in detail by Livefist here.

Speaking exclusively toLivefiston the LCA Tejas program, Defence Research & Development Organisation (DRDO) chief Dr. S. Christopher has welcomed the Defence Minister’s words.

“I am absolutely confident that the LCA Tejas Mk.2 will meet all requirements in a timely manner. I am also 100 per cent sure of further orders of not just the LCA Mk.1A but at least 200 of the Mk.2. Both of these aircraft will have tremendous export potential,” Christopher said.

Dr Christopher took a sortie in an LCA Tejas in January with IAF test pilot Air Vice Marshal A.P. Singh in the north east.

“The aircraft has matured wonderfully, to the full credit of our teams of engineers and scientists,” Christopher said. “It is a moment of great pride for us, but also a priority to see that the rest of the Tejas journey is very smooth.”

Thank GOD, now finally we have the Govt. who listen or give attention to the sentiments of the common people and take decisions in the national interest.

This was my tweet in November 2017.

Sorry for going off topic but I exactly don't know what's the status of Arjun Mk-II or how much Arjun Mk-II has been ordered. I pray to GOD to give some sense to our army to Firmly back the Arjun MK-II. Govt. Should have to look into this matter also like LCA TEJAS.

 

[Haldiram]

Thank GOD, now finally we have the Govt. who listen or give attention to the sentiments of the common people and take decisions in the national interest.

This was my tweet in November 2017.

View attachment 23613

Sorry for going off topic but I exactly don't know what's the status of Arjun Mk-II or how much Arjun Mk-II has been ordered. I pray to GOD to give some sense to our army to Firmly back the Arjun MK-II. Govt. Should have to look into this matter also like LCA TEJAS.

No one knows exactly how many Tejas and Arjun have been ordered. The OFB plants rumors in the media about X 100 orders, every once in a while. There's a turf battle between the forces and the DRDO-OFB bureaucracy.

See this debate :

 

[Galaxy 7]

HAL and ADA to blame here. I think HAL is intentionally slow in 20 IOC tejas production. Mainly due to the fact they failed in achieving FOC. So they will produce these 20 IOC tejas slowly till FOC is obtained

 

[tejas warrior]

Just not a medium one and that's why Yusuf is right, that it doesn't change anything for Tejas, which has it's own requirement in the light segment.

Tejas is India's ONLY Single Engine Fighter. AMCA will be Medium Range Fighter and till it arrives additional Rafale may be ordered.

Defence Minister Nirmala Sitharaman : “We are very confident that Tejas Mark II will be a big leap forward to fulfil the single engine fighter requirement of the forces,”

http://www.financialexpress.com/ind...raman/1086591/lite/?__twitter_impression=true

 

[tejas warrior]

This is what I foresee the IAF managing to get:
1. 300 + Tejas (all variants)
2. Another 36 Rafale under ToT.
3. Six squadrons of Sukhoi Su-57 derived FGFA ( provided Russia agrees to what India would want on this).

 

[Kharavela]

MK84 dumb bomb:
Weight 2039 lb (925 kg)
Length 129 in (3280 mm)

GBU 31 (MK84 dumb bomb + JDAM kit):
Length: (JDAM and warhead) GBU-31 (v) 2/B: 152.7 inches (387.9 centimeters); GBU-31 (v) 4/B: 148.6 inches (377.4 centimeters)
Weight: (JDAM and warhead) GBU-31 (v) 2/B: 2,036 pounds (925.4 kilograms); GBU-31 (v) 4/B: 2,115 pounds (961.4 kilograms);

How come Dumb Bomb MK84 weighs 2039 lb and GBU 31 v 2/B (MK84 dumb bomb + JDAM kit) weighs 2036 lb ?