HTT-40 Basic Trainer Aircraft: News & Discussions - 08 September 2019

Pratyush · Post by **Pratyush** » 13 Sep 2019 12:37

I would like very happy with IAF getting 106. With 220 export sales. I would be over the moon with joy.

Go fo it HAL, you can do it.

srin · Post by **srin** » 13 Sep 2019 14:03

I don't understand how HTT 40 will be better than attack helicopters for CAS. Other than top speed, what features does it have that would make it better ?

Bart S · Post by **Bart S** » 13 Sep 2019 16:29

srin wrote:I don't understand how HTT 40 will be better than attack helicopters for CAS. Other than top speed, what features does it have that would make it better ?

Not for CAS but for surveillance. Can very cheaply (compared with larger planes) do low level surveillance of land and coastal areas with a sensor suite attached and communication systems that can relay data to ground based operators. Great for border control, tracking infiltration and movement of insurgents, suspicious fishing vessels etc.

Weapons are purely optional, but if needed it can have Brimstone/APKWS type light precision weapons to take out high value targets. It's never going to be an A10

The Afghan air force uses Super Tucanos that the US military kitted out for them, and are quite happy with it.

fanne · Post by **fanne** » 13 Sep 2019 18:21

How about using uav that can be airborne for 24 hours, or even ucav- to squat occasional confirmed infiltration.
Lot cheaper, better and we are making few of them.

ashbhee · Post by **ashbhee** » 13 Sep 2019 18:51

srin wrote:I don't understand how HTT 40 will be better than attack helicopters for CAS. Other than top speed, what features does it have that would make it better ?

Cheaper to fly per hour
Fixed wing are cheaper to maintain
Fixed wing pilots are cheaper to train
Fast moving aircrafts are difficult to target using small arms

Bart S · Post by **Bart S** » 13 Sep 2019 19:00

fanne wrote:How about using uav that can be airborne for 24 hours, or even ucav- to squat occasional confirmed infiltration.
Lot cheaper, better and we are making few of them.

Cheaper how? The US and Israeli prices for them are eye watering. Plus there is no reason that both can coexist.

Anyways, it needs to be developed for the export market even if Indian forces dont want them.

LakshmanPST · Post by **LakshmanPST** » 13 Sep 2019 19:34

srin wrote:I don't understand how HTT 40 will be better than attack helicopters for CAS. Other than top speed, what features does it have that would make it better ?

Maybe slightly OT...
Saw this video just few days back about Turboprops that can be used as CAS...
Turboprops seem to have some advantages...
https://youtu.be/tSOlkj38FYA

tsarkar · Post by **tsarkar** » 13 Sep 2019 19:46

A humble request if this thread could be restricted to HTT-40 development, production & induction.

Weaponization and CAS can be discussed in design your own fighter thread.

Drones, Aerostats and Ground Based Radars surveil better.

Trainers are designed for ease of access to various mechanical, hydraulic and other systems for rapid & easy maintenance to ensure more students get more flying hours on them.

That very feature makes them very vulnerable to fire, including small arms.

Adding armour will require a more powerful & heavier engine and start an iterative spiral of development. Redesigning subsystems will reduce easy access for maintenance and it will no longer remain a trainer. Adding armour, new engine will cost more.

Which is why sending trainers to combat is a stupid idea. Like sending troops with bicycle instead of APC to war.

Many nations did deploy bicycles as it offered more mobility over marching troops. WW2 Japanese Army used bicycles extensively in Malaya and Singapore. But on the whole it was a stupid idea.

https://en.wikipedia.org/wiki/Bicycle_infantry

tsarkar · Post by **tsarkar** » 13 Sep 2019 19:57

Training is a very important function.

During the initial phase of WW2 in Pacific, both US & Japan lost 4 aircraft carriers each. The Japanese lost 4 carriers at Midway while the Americans lost USS Lexington at Coral Sea, USS Yorktown at Midway, USS Wasp & USS Hornet shortly thereafter.

Despite the losses, the US kept the carrier USS Ranger as a training carrier. The Japanese gradually ran out of well trained pilots while the US trained more and more pilots.

Training is a very important function requiring dedicated equipment and infrastructure that should not and must not be diluted nor diverted to other functions, no matter what.

Indranil · Post by **Indranil** » 13 Sep 2019 20:11

As much as I agree with you, weaponization and surveillance has been a stated goal of the HTT-40 program.

Bhaduria has already said that he has asked for funds to develop the weaponized version.

Kartik · Post by **Kartik** » 14 Sep 2019 00:09

And if HAL wants to export a weaponized version of the HTT-40 to nations that cannot afford fast jets, then nothing wrong with that either. For e.g., does Sri Lanka need fast jets? Or can an armed HTT-40 do the job for its Air Force? The success that the Super Tucano has seen has spurred on companies to develop armed variants of even crop dusters for export.

BTW, does it make sense to have an armed FAC variant for the Indian Army? 1971 saw Major Atma Singh win a MVC for his role as FAC in a Krishak. But that role could probably be performed by LCH or Apache gunships as well in the role of an armed scout/recon.

Anyhow, we are at a point where we could develop an armed variant and provide the airplane and the weapons as well. An armed HTT-40 carrying 4-6 Helina or a mix of Helina and rocket pods be used. Maybe even Mistral.

JayS · Post by **JayS** » 14 Sep 2019 22:07

As I posted earlier, 220 orders expected from non-IAF customers. May be HAL knows something that we don't like some customers actually expecting interest in armed HTT-40.

Philip · Post by **Philip** » 14 Sep 2019 22:24

HTT-40 will become the aircraft of choice of the flying clubs across the country. That's a v.big market considering the requirement for thousands of civilian airline pilots alone who have to learn on a BT.. Though increasinhly drones ard taking over duties like crop spraying and for surveillance militarily, a manned light bird like it will still have its uses for the IA, especially the armed version.

The cost of one Apache is and would be several times that of an armed BT.Just 6 Apaches for the IA is costing us overall $100M a pop! An armed HTT-40 would not cost more than $10M, plus being far easier to maintain and operate.This is not yo say that ig can be a replacement gor an attack helo, but adds to the IA's capabilities. The success of the LCH is nevertheless paramount for the IA no matter how useful the armed HTT is.

Indranil · Post by **Indranil** » 14 Sep 2019 22:36

Phillipji HTT40 is too much of an aircraft for most pilots at flying clubs. Hansa would be that aircraft. I dont know what happened to NM5, but that is another aircraft with great potential.

Philip · Post by **Philip** » 15 Sep 2019 08:42

An armed HTT would be very useful in sanitising border areas like Burma, Bdesh and the NE states, apart from our borders with Pak, where there are constant attempts to sneak in terrorists and insurgents. Our " own people", the Naxals/ Maoists have also been responsible for the deaths of hundreds of CRPF and police personnel, more per year perhaps than terrorists from across the border.They do NOT deserve soft treatment whatsoever.An HTT armed with a gunpod and lightweight
rockets would be ideal to prosecute them and reach hot spots far faster than by any force on the ground susceptible to IEDs.

vivek_ahuja · Post by **vivek_ahuja** » 15 Sep 2019 11:05

IMO, all this talk of armed HTT and surveillance HTT is not worth the time discussing it.

The surveillance platform should be an unmanned UAV that can stay aloft for a much longer time; make a lot less noise; require lot less fuel and maintenance, etc..

The armed platform cannot survive in anything other than bushwhacking some rebels or in COIN, which India is not in need of. There might be some export users for it, but India (and HAL) does not have the skill-set and wherewithal to become a global arms competitor at that level. Too many PSU-like weaknesses for that kind of product support and delivery to third-party non-GOI customers.

I will be happy of the HTT can be delivered in numbers in its primary role as a trainer for the IAF (and perhaps some other air forces) and kill this external dependency on the Pilatus etc.

pushkar.bhat · Post by **pushkar.bhat** » 15 Sep 2019 11:11

An Armed HTT-40 has only one utility - as a trainer. You can train pilots to use weapons using a low-cost platform. SMART is aimed at meeting this very purpose.

Gyan · Post by **Gyan** » 15 Sep 2019 11:36

Would HTT40 be useful for CAS in mountains due to its slower speed & better turning radius compared to jet aircraft or vulnerable helicopters?

Haridas · Post by **Haridas** » 17 Sep 2019 11:32

Gyan wrote:Would HTT40 be useful for CAS in mountains due to its slower speed & better turning radius compared to jet aircraft or vulnerable helicopters?

Unpredictable tempest type winds (strong downdraft) of mountains make light & slow HTT40 a less useful craft, even unnecessary risk.

ashishvikas · Post by **ashishvikas** » 18 Sep 2019 09:02

IAF may order 70 basic trainers made by HAL

https://m.hindustantimes.com/india-news ... QyBfP.html

The Indian Air Force (IAF) plans to start the official process within three months for the possible purchase of 70 locally produced basic trainers from state-owned aircraft maker Hindustan Aeronautics Limited (HAL), three senior IAF officers said on condition of anonymity.

IAF is set to send a request for proposal (RFP) to HAL for the indigenous Hindustan Turbo Trainer-40 (HTT-40) before the end of the year, they added.

“The HTT-40 has entered the final stages of rigourous testing. The air force is optimistic that the trainer will meet its requirements. If all goes well, the RFP will be out by the year-end,” said one of the officials cited above who asked not to be named.

The HTT-40 is currently undergoing a string of elaborate tests at HAL to demonstrate that it is safe for rookie pilots and meets IAF’s exacting standards for trainer planes. Test pilots have wrapped up intensive flight tests but some brutal trials are yet to be conducted, said a second official.

A few days ago, the aircraft successfully completed the six-turn spin (towards the right), recovering from an uncontrolled flight using conventional methods. “The next stage of trials will be critical as it involves testing the HTT-40’s spin behaviour in the left direction, which is far more complicated,” the second official said.

If the remaining tests go smoothly, HAL could begin production by early 2021, said a third official tracking the air force’s modernisation drive. IAF, however, is clear that it does not want a piecemeal delivery of the basic trainers. “We don’t want HAL to deliver the aircraft in ones and twos as that will not meet our training requirements. We would need at least 20 planes to begin training. According to our estimates, it will take HAL around four years to deliver that number,” the third official added.

To facilitate the release of the RFP this year, IAF plans to seek a fresh Acceptance of Necessity (AoN) from the defence acquisition council to pursue the HTT-40 purchase under the Defence Procurement Procedure (DPP) 2016 instead of DPP-2008, which currently covers it. “That’s important because under DPP-2008, user trials have to be conducted before the RFP is issued. However, the provisions of DPP-2016 allow the RFP to come before the user trials,” said the second official cited above.

The upcoming RFP may also allow HAL to release around $25 million to upgrade the Honeywell TPE331-12B turboprop engine that powers the basic trainer to extract maximum performance from the aircraft, said the first official. HAL was reluctant to spend on the upgrade unless the order came through.

Rookie pilots in IAF go through a three-stage training involving the Pilatus PC-7 MkII planes, Kiran trainers and finally the Hawk advanced jet trainers before they can fly fighter jets. As the Kirans are approaching the end of their service life, some amount of Stage 2 training is being done on the PC-7.

The defence ministry in July suspended business dealings with Pilatus Aircraft Limited for one year for violation of a pre-contract integrity pact in a ~2,900-crore contract for 75 basic trainers, and also factoring in ongoing Indian investigations against the Swiss plane maker for alleged corruption and irregularities.

The contract included a follow-on purchase of 38 more planes, but the ban means IAF can’t invoke the clause. The order for additional planes could be sourced from HAL, said a fourth IAF official. Experts welcomed IAF’s decision to take the HTT-40 purchase forward. “It’s a big thumps up to indigenisation and the RFP is an indicator that the locally made trainer will meet IAF’s requirements. It is now up to HAL to meet the timelines and provide adequate technical support. It has been found wanting in some of those aspects in the past,” said Air Vice Marshal Manmohan Bahadur (retd), additional director general, Centre for Air Power Studies.

Neela · Post by **Neela** » 18 Sep 2019 11:02

We don’t want HAL to deliver the aircraft in ones and twos as that will not meet our training requirements. We would need at least 20 planes to begin training. According to our estimates, it will take HAL around four years to deliver that number,” the third official added.

20 planes in one go for a new product first production run?

JayS · Post by **JayS** » 18 Sep 2019 12:06

20 plans to start training syllabus. That's fair bit of number. The requirement of flying hours is very high.

tsarkar · Post by **tsarkar** » 18 Sep 2019 13:08

Kartik wrote:For e.g., does Sri Lanka need fast jets?

At the beginning of the Tamil Insurgency and even before that the Sinhala JVP insurgency, Sri Lankans used their Sia Marchetti SF260 trainers that were chopped up by simple 7.62 mm PK machine gun fire. Reasons for chop up in my earlier post. They then acquired Mi-17 & Mi-35 that were targeted by MANPADS. Finally they got MiG-27 and Kfir that were instrumental in their final success.

tsarkar · Post by **tsarkar** » 18 Sep 2019 13:12

The biggest contributor to defence indigenous production has been corruption. Makes one laugh and cry at the same time.

Neela · Post by **Neela** » 18 Sep 2019 13:29

JayS wrote:20 plans to start training syllabus. That's fair bit of number. The requirement of flying hours is very high.

Dont want to turn this into a rant. But getting 20 from an order of 70 odd in one go is unrealistic -financially and logistically. THere are going to be issues in parts sourcing, in QA , during final assembly , , , during testing, during initial adoption . Even after delivery, there will be issues from the user. All these need to be sorted out to get a stable line that can churn out numbers.

chetak · Post by **chetak** » 18 Sep 2019 14:40

Neela wrote:
JayS wrote:20 plans to start training syllabus. That's fair bit of number. The requirement of flying hours is very high.
Dont want to turn this into a rant. But getting 20 from an order of 70 odd in one go is unrealistic -financially and logistically. THere are going to be issues in parts sourcing, in QA , during final assembly , , , during testing, during initial adoption . Even after delivery, there will be issues from the user. All these need to be sorted out to get a stable line that can churn out numbers.

maybe the dwindling availability of the kirans and the pilatus imbroglio has put a great deal of pressure on the IAF for training resources.

srai · Post by **srai** » 18 Sep 2019 15:44

^^^
Still waiting for RFP

mody · Post by **mody** » 18 Sep 2019 17:12

I think what the "20 in one go" type thing means is that IAF can start training with HTT-40 only when minimum 20 aircrafts are available with them, not when only 2-4 planes are delivered. Hence, they would want the delivery time to be very fast.
Offcourse the unnamed source then goes on to add, that as per his/their expert opinion, it would take HAL 4 years to deliver 20 planes, after receipt of the PO. This was part of the usual bullshit or the said unnamed source, just venting pent up frustration with HAL.

Then comes this "Experts welcomed IAF’s decision to take the HTT-40 purchase forward. “It’s a big thumps up to indigenisation and the RFP is an indicator that the locally made trainer will meet IAF’s requirements. It is now up to HAL to meet the timelines and provide adequate technical support. It has been found wanting in some of those aspects in the past,” said Air Vice Marshal Manmohan Bahadur (retd), additional director general, Centre for Air Power Studies."

Shows that IAF over the years has been frustrated with HAL quality and service and hence were against HAL developing the HTT-40 from the outset.
However, with the speed with which the HTT-40 has come about and the build quality of the Tejas, that have been rolling of the new assembly lines at HAL, it seems things are improving at HAL.
Specifically for HTT-40, I would certainly cut HAL some slack and look forward to expedited delivery and induction of the planes in IAF inventory.

The numbers should be increased from 70 to 106, as was originally planned.

vishvak · Post by **vishvak** » 18 Sep 2019 17:17

Just making an OT point here that one can't put gearbox of HTT-40 in Saras and make it fly like HTT-40. But in case of need, one can replace gearbox of Saras on HTT-40 or in other words downgrade HTT-40 for peacetime purposes.

Indranil · Post by **Indranil** » 18 Sep 2019 21:01

vishvak wrote:Just making an OT point here that one can't put gearbox of HTT-40 in Saras and make it fly like HTT-40. But in case of need, one can replace gearbox of Saras on HTT-40 or in other words downgrade HTT-40 for peacetime purposes.

I don't understand what you are saying. These airplanes are not lego pieces. To give you an example, the reason for the Saras crash was a slight mismatch of engine and propeller configurations. Pratt and Whitney and MT (propeller OEM) had both conveyed to NAL that the engine propeller combo was safe, but they missed out a detail on feathering and another prop position for relight.

From Sara to HTT-40, the engine is different, the direction of rotation is different, the prop maker is different. You can't just mix and match these things.

vishvak · Post by **vishvak** » 18 Sep 2019 21:07

Indranil wrote:..
I don't understand what you are saying. These airplanes are not lego pieces. To give you an example, the reason for the Saras crash was a slight mismatch of engine and propeller configurations. Pratt and Whitney and MT (propeller OEM) had both conveyed to NAL that the engine propeller combo was safe, but they missed out a detail on feathering and another prop position for relight.

From Sara to HTT-40, the engine is different, the direction of rotation is different, the prop maker is different. You can't just mix and match these things.

Ok, sorry for OT. My emphasis was to downgrade or limit performance.. so gearbox is all that is needed to be replaced IF need arises.. is all. It could be the same gearbox as well.. nothing to do with Saras actually. At this point of time that is what is needed prolly i.e. to have more trainers production wise and to find out domestic customers in some possible way.

Indranil · Post by **Indranil** » 18 Sep 2019 22:06

RANT
It may be bad reporting, but if the reporter has captured the tone of the IAF officer correctly, then it is quite unfortunate. What did the HTT-40 team do wrong? That they dreamt to come up with world class turbotrainer with limited experience? Or that they expected preferential treatment from their own airforce and got none? Forget preferential treatment, every opportunity was taken to kill the project and disparage the team.

I mean look at it now. They toiled hard for ten years and they just succeeded in doing something that nobody in India has done since the design days of HPT-32. HTT-40 is a worldclass trainer at par with the PC-9, Texan-II Tucano and the KT-1. What is the point of showing this project is bad light now?
And IAF's linen is not very clean in this BTT procurement project.

This attitude of customer is king should die. We are in the same team. Working for the defense of this country.

ramana · Post by **ramana** » 18 Sep 2019 22:28

Indranil wrote:~~RANT~~
It may be bad reporting, but if the reporter has captured the tone of the IAF officer correctly, then it is quite unfortunate. What did the HTT-40 team do wrong? That they dreamt to come up with world class turbo-trainer with limited experience? Or that they expected preferential treatment from their own air force and got none? Forget preferential treatment, every opportunity was taken to kill the project and disparage the team.

I mean look at it now. They toiled hard for ten years and they just succeeded in doing something that nobody in India has done since the design days of HPT-32. HTT-40 is a world class trainer at par with the PC-9, Texan-II Tucano and the KT-1. What is the point of showing this project is bad light now?
And IAF's linen is not very clean in this BTT procurement project.

This attitude of customer is king should die. We are in the same team. Working for the defense of this country.

I second your informed comment. Its not a rant. So I did strike through.

To me its interesting that there are four IAF officers who decided to comment on the HTT-40.
Of them the worst is the unnamed third official.
He wants HAL to deliver 20 planes at one go!

If the remaining tests go smoothly, HAL could begin production by early 2021, said a third official tracking the air force’s modernisation drive. IAF, however, is clear that it does not want a piecemeal delivery of the basic trainers. “We don’t want HAL to deliver the aircraft in ones and twos as that will not meet our training requirements. We would need at least 20 planes to begin training. According to our estimates, it will take HAL around four years to deliver that number,” the third official added.

Aircraft are not like potato chips to be made and stocked.
The delivery is as the planes roll off.

This 20 planes requirement means HAL has to make the planes and stock them and the IAF will pay after the delivery of those twenty at one go.
In meantime HAL will accumulate inventory costs and the whole supply chain will get affected. Wont get paid for three to four years to satisfy this person's ego and pique.

This person is a master of the art of successful sabotage.
Refer to the OSS manual I had posted long back.

Link: https://www.businessinsider.com/oss-man ... ty-2015-11

"Some of the instructions seem outdated; others remain surprisingly relevant," reads the current introduction on the CIA's site. "Together they are a reminder of how easily productivity and order can be undermined."

We've collected below some of the timeless instructions on how to be a terrible employee. What's most amusing is that despite the dry language and specificity of the context, the productivity-crushing activities recommended are all-too-common behaviors in contemporary organizations everywhere.

See if any of those listed below — quoted but abridged — remind you of your boss, colleagues, or even yourself.

Organizations and Conferences

Insist on doing everything through "channels." Never permit short-cuts to be taken in order to expedite decisions.
Make "speeches." Talk as frequently as possible and at great length. Illustrate your "points" by long anecdotes and accounts of personal experiences.
When possible, refer all matters to committees, for "further study and consideration." Attempt to make the committee as large as possible — never less than five.
Bring up irrelevant issues as frequently as possible.
Haggle over precise wordings of communications, minutes, resolutions.
Refer back to matters decided upon at the last meeting and attempt to re-open the question of the advisability of that decision.
Advocate "caution." Be "reasonable" and urge your fellow-conferees to be "reasonable"and avoid haste which might result in embarrassments or difficulties later on.

Managers

In making work assignments, always sign out the unimportant jobs first. See that important jobs are assigned to inefficient workers.
Insist on perfect work in relatively unimportant products; send back for refinishing those which have the least flaw.
To lower morale and with it, production, be pleasant to inefficient workers; give them undeserved promotions.
Hold conferences when there is more critical work to be done.
Multiply the procedures and clearances involved in issuing instructions, pay checks, and so on. See that three people have to approve everything where one would do.

Employees

Work slowly.
Contrive as many interruptions to your work as you can.
Do your work poorly and blame it on bad tools, machinery, or equipment. Complain that these things are preventing you from doing your job right.
Never pass on your skill and experience to a new or less skillful worker.

When the requirement is 106, they settle for 60 and then want 20 planes at one go!!!

Note he is in charge of IAF modernization.
No wonder it lags.

Folks the next person who talks about armed HTT-40 will get banned.
Don't make a useful thread into a nukkad.

Jayram · Post by **Jayram** » 18 Sep 2019 22:56

A few days ago, the aircraft successfully completed the six-turn spin (towards the right), recovering from an uncontrolled flight using conventional methods. “The next stage of trials will be critical as it involves testing the HTT-40’s spin behavior in the left direction, which is far more complicated,” the second official said.

I was curious as to why it would be different on the left and right. Turns out one of the reasons is the propeller direction has a effect on the spin rate with spin being more in the direction of the propeller spin. Here it is taken verbatim from a research paper "It was also noted that for a given fuel load, a spin to the
right is faster than to the left due to the yawing effect of the propeller."
From here
https://pdfs.semanticscholar.org/b9ad/e ... 3f8470.pdf

More information required from Gurus here to definitely decide how much of a risk this is in the development of our nascent trainer.

chetak · Post by **chetak** » 18 Sep 2019 23:50

Jayram wrote:
A few days ago, the aircraft successfully completed the six-turn spin (towards the right), recovering from an uncontrolled flight using conventional methods. “The next stage of trials will be critical as it involves testing the HTT-40’s spin behavior in the left direction, which is far more complicated,” the second official said.
I was curious as to why it would be different on the left and right. Turns out one of the reasons is the propeller direction has a effect on the spin rate with spin being more in the direction of the propeller spin. Here it is taken verbatim from a research paper "It was also noted that for a given fuel load, a spin to the
right is faster than to the left due to the yawing effect of the propeller."
From here
https://pdfs.semanticscholar.org/b9ad/e ... 3f8470.pdf

More information required from Gurus here to definitely decide how much of a risk this is in the development of our nascent trainer.

It has to do with the direction of rotation of the propeller, just like it says.

Jayram ji, kindly google the rest.

JayS · Post by **JayS** » 19 Sep 2019 00:57

Jayram wrote:
A few days ago, the aircraft successfully completed the six-turn spin (towards the right), recovering from an uncontrolled flight using conventional methods. “The next stage of trials will be critical as it involves testing the HTT-40’s spin behavior in the left direction, which is far more complicated,” the second official said.
I was curious as to why it would be different on the left and right. Turns out one of the reasons is the propeller direction has a effect on the spin rate with spin being more in the direction of the propeller spin. Here it is taken verbatim from a research paper "It was also noted that for a given fuel load, a spin to the
right is faster than to the left due to the yawing effect of the propeller."
From here
https://pdfs.semanticscholar.org/b9ad/e ... 3f8470.pdf

More information required from Gurus here to definitely decide how much of a risk this is in the development of our nascent trainer.

Actual difference in values is like 5%. I dont think pilot would even notice such difference.

IMO the issue is related to the recovery, not the spin itself. Typically single prop aircrafts in the West have clockwise rotating engine and thus the prop, when looked from cockpit. A clockwise rotating prop, in nose down movement, as is required during recovery from the spin, to reduce AoA, would produce a left yaw-ing torque due to its gyroscopic effect. Thats a pro-spin moment for a left spin. So it would make the recovery comolicated.

But I am not 100% sure this is the only thing involved here.

JayS · Post by **JayS** » 19 Sep 2019 01:13

ramana wrote:
Aircraft are not like potato chips to be made and stocked.
The delivery is as the planes roll off.

This 20 planes requirement means HAL has to make the planes and stock them and the IAF will pay after the delivery of those twenty at one go.
In meantime HAL will accumulate inventory costs and the whole supply chain will get affected. Wont get paid for three to four years to satisfy this person's ego and pique..

Can we for a second think that it could be the DDM writing crap?

I think, There is nothing wrong in saying they need 20 aircrafts min to push it into training syllabus. They need enough numbers to fulfil the significantly high number of hours per batch and enough nos for entire batch or at least like half batch or so. They cannot mix and match it with Pilatus as the Trainees need to memorize cockpit of any aircraft before they can even sit in it. Having to deal with two types in stage 1 would be too much burdon. Hence IAF academy needs good number to boot and it makes sense to me at least. But I dont think that necessarily mean they will not take deliveries until 20 are made. IAF needs to train the trainers first. I think initial few deliveries will be used for that, till sizable inventory is built up.

JayS · Post by **JayS** » 19 Sep 2019 01:14

MOD NOTE - I did second round of clean up. If you see your posts are poofed, you'd know they were OT.

Rakesh · Post by **Rakesh** » 19 Sep 2019 01:23

JayS wrote:MOD NOTE - I did second round of clean up. If you see your posts are poofed, you'd know they were OT.

Please hand out short term bans during the third round.

Jayram · Post by **Jayram** » 19 Sep 2019 01:46

JayS wrote:
Jayram wrote: I
Actual difference in values is like 5%. I dont think pilot would even notice such difference.

IMO the issue is related to the recovery, not the spin itself. Typically single prop aircrafts in the West have clockwise rotating engine and thus the prop, when looked from cockpit. A clockwise rotating prop, in nose down movement, as is required during recovery from the spin, to reduce AoA, would produce a left yaw-ing torque due to its gyroscopic effect. Thats a pro-spin moment for a left spin. So it would make the recovery comolicated.

But I am not 100% sure this is the only thing involved here.

Now that is helpful thanks. So harder milestone coming up.