Indian Military Aviation - 21 Sept 2015

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Re: Indian Military Aviation - 21 Sept 2015

Postby Shreeman » 14 Jan 2016 20:16

Phillip,

There appears to be no reason or rhyme in your persistence. The total IJT development budget with all delays appears to be 400+ crores over 15 years and it has produced a sozen or so prototypes. The total development cost of HTT (3 prototypes) is 300+ crores. Those are first google search numbers.

That alone should show the futility of your arguments. Real defence contracts are two orders of magnitude larger, say several thousand crores for the PC over many fewer years and several tens of thousands of crores for any fighter/jet trainer.

If the LCA/FGFA are supposed to be prioritized to 10,000s crores then just what would 100s crores really add to this effort? You do understand even this is spread of many years. So the dissolution of BOTH projeCts may add 10s of crores a year AT BEST to their 1000s crore budget per year. That is not even inflation or interest worthy.

The CAG is selective in what it investigates. Its job is to locate inefficiencies, even if it is a penny. Quoting it without context is ridiculous. You try a shoestring budget, you get a shoestring, not the shoe.

What has gone wrong with you?

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Re: Indian Military Aviation - 21 Sept 2015

Postby Indranil » 14 Jan 2016 22:33

Philip sir,

1. Do you want the number of fatalities on other planes in the IAF inventory?
2. CAG is right that a plane designed in and built mostly in the 1970s/early 80s is really long in the tooth in 2009. But HAL cannot be blamed for that.
3. For the first time HAL is not waiting on the customer. They are doing things on their own. The engines, the HTT-40, the 10-seat commuter plane are all steps in that direction. And the govt. is supporting them. That is great!

No more on this from me.

I think you are speaking of the Tigerfish retractable floats. I don't know if HAL is contracting them. They might just go for fixed floats.

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Re: Indian Military Aviation - 21 Sept 2015

Postby member_29268 » 15 Jan 2016 00:59

@indranil,
The new tail configuration might have to do with spin recovery. See this video at 2:30 https://www.youtube.com/watch?v=dCG5xdy4k10 . It seems that this particular configuration results only in steep spin and not the flat one. Also T tail has problems with early stall but has little to do with spin recovery i guess.

@Philip,
It will be waste of money and development efforts (Once again!) if any of the current programs are scrapped. I do agree though that HAL has too many projects in its hand and in the absence of strong program management team/user support/user interest some of the projects are suffering. But solution can never be to scrap those projects. IAF has played spoiled kid for a long time now. A project will always be mediocre if the user has no role in providing the crucial feedback required during the development phase. I also agree that HAL should be able to design and develop the trainer type aircrafts in a shorter span of time due to it having designed and developed a number of trainer aircrafts. I don't understand though that why the problems in HPT-32 were not eliminated and if IAF’s feedback was taken/IAF gave feedback. Blame game only ends when Maaalik decides to end it and of course Maaalik has to have interest.

The Q still being asked is why some advanced air forces have only a 2-stage regime?They operate only 2 types not 3. Surely cost saving is evident there?


probably if IAF had money that Advanced forces have they might have been doing training in two phases instead of three. But still again flying more types of planes, as Indranil pointed out leads to smoother transition plus more experience (read variety).

We are v.shortstaffed in aerospace HR,our assets must be used for the most important programmes esp trainers the foundation of the IAF's pilot trg. capabilities.


I don’t believe that it has anything to do with short staffing .. problem lies in mis management of resources . i have had first hand experience with this.

There is not a financial connection, material connection, or man power connection.


There is a connection with respect to priority.. Why then if design and development staff,funding being different we still take so much time to build the prototypes. Apart from insufficient user support the second big problem is that same place (read same machines?) is used for production and development and obviously production takes priority over development project when there is no-one pushing from the top. Agree with Indranil that ownership brings responsibility. Ask the IAF that they have to take HTT-40 in equal numbers as the PC-21. Remember how IAF agreed with ordering 100 odd Mk1As.


our point should be establish capacity, an expanding one. Growing to meet growing economic needs. Not contracting to meet some critical minimal needs. The top priority ought to be a large enough ecosystem to produce what is need in this generation and the next.

It is an extremely misguided thought that "our assets" working on project A, can somehow make "project B" work better. You can divert salaries (not possible in public sector in practice) and you can hir appropriate minds for each project (eXtra cost). The practice of trying to fit square pegs (existing employee with skills for A ) into round hole (skills needed for is what needs to this "doing it first time" and "it will take time as learning curve onlee". You can argue for increasing the resources for B so that it is not runat a cottage indhstry scale but there is nothing to be gained by railing against what has finally reached reality against the red tape inertia. The HTT, IJT have nothing at all to do with progress on FGFA and every other technology yet to be invented.

If you need resources, ask for them. Staff MTA, fund FGFA, build Saras, whatever. Some people do need four wives, they convert to the religion that facilitates it.

1. I fail to buy the argument that HAL will have different design teams for HTT-40,IJT and FGFA(if it comes through), AMCA etc..it does not makes sense not to use experienced designer for other projects. Correct me if indeed HAL has different design teams.

2. I wish it was as easy as you are making it "ASK and you shall have it".

Your opinion and mine don't matter. So it is futile of me to change your opinion. I am extremely happy that there is a raksha mantri today who can crack a whip and ask everybody to fall in line. That was missing all these years. And that is all that matters. By the way, he has been outspoken in his praise for the HTT-40. So ....


Indranil, Second that thought, this is the only thing which matters the most. You need someone who is knowledgeable to crack the whip. have seen things change overnight when someone at the top starts to do just that..cutting through all the bull**** of various brothers/cousins/chachas/kakas in the family.
2. CAG is right that a plane designed in and built mostly in the 1970s/early 80s is really long in the tooth in 2009. But HAL cannot be blamed for that.


HAL/IAF/MOD all have to be blamed for that. just because an aircraft was designed in 1970s does not mean that it should develop problems today(other than airframe fatigue which can be eliminated by manufacturing new ones).
3. For the first time HAL is not waiting on the customer. They are doing things on their own. The engines, the HTT-40, the 10-seat commuter plane are all steps in that direction. And the govt. is supporting them. That is great!

Totally agree.

As for HAL it suffers the criticism by trying to be a monopoly. If it would only separate itself into sufficient different entities (there is a spin off cycle in industry, and there is a consolidation cycle too) then those parts that have merit would escape unmerited criticism. As of now everyone is HAL. The criticism of IJT applies to HTT. The LUH state of affairs gets combined with ALH. Never mind IMRH.

come DPP-16 and things may not be same again. I Hope lots of sub-system level design and development work will be done by different entities and HAL will start acting as only Tier-1 contractor/system integrater only along with TATAs and L&Ts.

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Re: Indian Military Aviation - 21 Sept 2015

Postby Kartik » 15 Jan 2016 03:08

Aankhen sek lo..old pics apparently, posted on another forum.

Image

Image

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Re: Indian Military Aviation - 21 Sept 2015

Postby Shreeman » 15 Jan 2016 03:22

nirav,

You have asked a good question. What are the design capabilities and how are they distributed. Does anyone know what is in public domain, the websites are not helpful.

As for production, it is nearly impossible same material or machines or manpower are used. Heck the assembly lines are often not even in the same cities. And all this talk of creating and stabilizing assembly lines, using new manufacturing processes would be all moot if only one assembly line was in use.

You can be guaranteed that the LCA team at HAL is for instance insulated from HTT/IJT. I havent seen the HTT team being described in a long time (read through old MSM to check the occasional reference) but that seemed well separated from IJT too given their pressing and overlapping deadlines.

The concept of "A designer" is history now, and aeronautical engineering is no longer a one person can learn all field, experience or not. You would assume there would be bunches of scientists garde a,b,c,d etc in each separate team.

edit -- I left out the response to elastic timelines question. To a lay person it is the fear of obvious waste (part worth X crore was bought and it rusted now who gets the blame? ), b) inefficiencies in the tendering, and c)lack of understanding/access to the global aviation protyping marketplace. The system is not setup for responding to needs. The overall purpose is still to act as plan B to import and as a front for "absorbing ToT". In short, more often the timelines are elastic by design.
Last edited by Shreeman on 15 Jan 2016 03:28, edited 1 time in total.

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Re: Indian Military Aviation - 21 Sept 2015

Postby Kartik » 15 Jan 2016 03:25

Vayu Aerospace article snippet

Hawks of Dega

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Re: Indian Military Aviation - 21 Sept 2015

Postby Karan M » 15 Jan 2016 05:18

Ugly brute that MiG upgrade.

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Re: Indian Military Aviation - 21 Sept 2015

Postby Shameek » 15 Jan 2016 05:40

Always loved the lines of the original Fulcrum. This one, not so much. :)

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Re: Indian Military Aviation - 21 Sept 2015

Postby Singha » 15 Jan 2016 08:50

love the hunched over general grevious look

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Re: Indian Military Aviation - 21 Sept 2015

Postby BharadwajV » 15 Jan 2016 08:57

What is that Bulge between the intakes?

And the A2A Refuelling probe looks like it's from an RAF Tornado!
The 29K has a cleaner unit.
Image

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Re: Indian Military Aviation - 21 Sept 2015

Postby Shameek » 15 Jan 2016 09:23

What is that Bulge between the intakes?


Centerline fuel tank.

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Re: Indian Military Aviation - 21 Sept 2015

Postby shiv » 15 Jan 2016 09:24

BharadwajV wrote:What is that Bulge between the intakes?

Do you want me to say what it is or what I think it looks like? :D

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Re: Indian Military Aviation - 21 Sept 2015

Postby Philip » 15 Jan 2016 12:04

Q.Can the IN's Hawks be armed...with AAMs,ASMs or even LW ASW torpedoes,like those which our ASW helos use. They would be most valuable assets in any crisis,giving the IN extra assets to prosecute enemy ships,subs or even aircraft threatening the mainland/islands.

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Re: Indian Military Aviation - 21 Sept 2015

Postby BharadwajV » 15 Jan 2016 12:53

BAe had proposed the combat Hawk upgrade for the IAF's Mk.132s but they surely will ask an arm and several legs.
They could be armed with ASRAAMs for A2A, Sea Eagles for Anti-Ship and Brimstones for A2G.
Don't think the IN would want an aircraft with short legs for operations especially since we have P-8Is and Sea Dragons for these very roles.
And for coastal defence we could use more BrahMos missiles since they are effective and importantly in production.
Not to mention the 45 MiGs each of which can carry over two AShMs.
We however need Multi mission choppers embarked on Warships.
We could also use more ASuW Aircraft that are less expensive, possibly the C295W with additional sensors?
We need to harass Pakistani Submarines day in and day out and keep an eye (or sixty) out for PLA-N Subs.

Does the NauSena operate Basic Trainers of it's own?
They have Kiran and Hawk for the remaining stages, though...

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Re: Indian Military Aviation - 21 Sept 2015

Postby Aditya G » 15 Jan 2016 13:24

For starters, IN could weaponize Hawks to perform following missions:

- Defensive CAPs over naval air stations
- Counter UAV missions

Perhaps, a trainer variant similar to Goshawk can be developed for arrestor wire landing.

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Re: Indian Military Aviation - 21 Sept 2015

Postby BharadwajV » 15 Jan 2016 15:27

Aditya G wrote:Perhaps, a trainer variant similar to Goshawk can be developed for arrestor wire landing.

No need Saar.
The N-LCA brings a can of Whoop Ass on this front. (Supersonic, MMR, full Weapons Suite, Hands Off Take-off etc )
Hopefully the progression line would be BTA-Kiran-Hawk-N LCA-MiG 29K.
The NauSena operates a fairly small fleet of Hawks. I'd much rather see the AF get the combat package.

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Re: Indian Military Aviation - 21 Sept 2015

Postby Nick_S » 15 Jan 2016 16:23


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Re: Indian Military Aviation - 21 Sept 2015

Postby Aditya G » 15 Jan 2016 17:16

^ KH-29L

Note that it is a 2 seater variant.

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Re: Indian Military Aviation - 21 Sept 2015

Postby deejay » 15 Jan 2016 17:41

Anyone heard of LCA in UCAV mode programme being discussed at HAL and ADA - ULCAV?

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Re: Indian Military Aviation - 21 Sept 2015

Postby sarang » 15 Jan 2016 19:58

whats on canopy?

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Re: Indian Military Aviation - 21 Sept 2015

Postby shiv » 15 Jan 2016 20:41

sarang wrote:whats on canopy?

It is a mirror although I am not sure of its purpose. It probably gives a better view of what is below and in front of the nose at Hi AoA while landing

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Re: Indian Military Aviation - 21 Sept 2015

Postby Indranil » 15 Jan 2016 21:42

That's right. It is a periscope for the instructor to check the flow during landing and take off.

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Re: Indian Military Aviation - 21 Sept 2015

Postby Indranil » 16 Jan 2016 01:25

khedar wrote:@indranil,
The new tail configuration might have to do with spin recovery. See this video at 2:30 https://www.youtube.com/watch?v=dCG5xdy4k10 . It seems that this particular configuration results only in steep spin and not the flat one. Also T tail has problems with early stall but has little to do with spin recovery i guess.

What a fabulous video. Thank you!

But I think that IJT does enter a flat spin. This has been specified explicitly in the paper "Aircraft Performance Improvements- A practical approach".

This may be because the CG is much further back along the MAC than that of the models shown in the video. Also, IJTs tail assembly is different from the model shown at 2:30. In IJT's case, the horizontal stabilizer is actually pushed back along the longitudinal axis, rather than brought forward as studied in the model. Also, the tail and the wings on the IJT are less longitudinally and more vertically spaced. Now, consider the smoke flow around 6:15. Imagine IJT's case. If the tail is closer to the wing longitudinally, and spaced wider vertically, then it would lie in the wake of the wing, which would affect recovery.

In fact it is known that original IJT prototypes were unlikely to be able to recover from flat spin. Adding the nose strakes and the dorsal fins allowed recovery in the wind tunnel. The prototypes at Aero India also showed wing fences. All these validated news reports that HAL was trying to contain a wing drop before stall. However, the effectiveness of these solutions on the real plane became questionable when one the prototypes crashed while flight testing. Later pictures showed LSPs in flight testing with spin chutes. Interestingly, in those pictures, the nose strakes and wing fences were missing, and vortex generators appeared on the outboard section of the wing. However, the plane continued to stall too early, and drop the wing.

The final word is that HAL identified the location of the airflow separation. Additionally, on BAE's suggestion, they added weights to the wingtips to increase the roll inertia. These have led to satisfactory results. There was some paanwalla/chaiwalla hearsay to the contrary, but our Sanjay's on the HAL boundary are reporting regular sightings of the bird. That can only mean something good.

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Re: Indian Military Aviation - 21 Sept 2015

Postby Kartik » 16 Jan 2016 03:24

Singha wrote:love the hunched over general grevious look


me too..the Fulcrum is IMO, the most beautiful bird ever designed and even the SMT upgrade cannot make it look ugly to me.

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Re: Indian Military Aviation - 21 Sept 2015

Postby Surya » 16 Jan 2016 04:40

Kartik wrote:
Singha wrote:love the hunched over general grevious look


me too..the Fulcrum is IMO, the most beautiful bird ever designed and even the SMT upgrade cannot make it look ugly to me.


+100

if a substantial part of the supply chain could be shifted to India - I would not mind MKIzed fulcrums or the 29K land versions

for topping up the fleet in lieu hard to get M2Ks

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Re: Indian Military Aviation - 21 Sept 2015

Postby shiv » 16 Jan 2016 06:29

khedar wrote:@indranil,
See this video at 2:30 https://www.youtube.com/watch?v=dCG5xdy4k10

The video starts with a vertical wind tunnel.

Now how difficult would it be to construct something similar. Variable speed fan blowing air up through a net to catch the plane when it falls.

Why were models sent to France for vertical wind tunnel tests?
Why does India not have a vertical wind tunnel? (or do we have a few now?)

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Re: Indian Military Aviation - 21 Sept 2015

Postby member_29268 » 16 Jan 2016 18:14

^^ can't recall if ever heard about vertical wind tunnel in India. besides it needs to have some scientific application for our shodh establishments to erect one. Other than spin testing I can only think of skydiving practice as another potential application for such a tunnel (might be useful for our special forces though 8) ).

http://aerodium.technology/en/models/models/recirculation/

It seems to be pretty expensive, though a desi tunnel may cost a lot less. Also could be used to recover the capital costs by providing joy sky diving experiences in the initial years.

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Re: Indian Military Aviation - 21 Sept 2015

Postby shiv » 16 Jan 2016 20:14

khedar wrote:^^ can't recall if ever heard about vertical wind tunnel in India. besides it needs to have some scientific application for our shodh establishments to erect one. Other than spin testing I can only think of skydiving practice as another potential application for such a tunnel (might be useful for our special forces though 8) ).

http://aerodium.technology/en/models/models/recirculation/

It seems to be pretty expensive, though a desi tunnel may cost a lot less. Also could be used to recover the capital costs by providing joy sky diving experiences in the initial years.

A vertical wind tunnel appears pretty simple to do. I heard a description from Air Marshal Rajkumar of the one in France that was used by India. I tried to make one at home - but I now realize that It needs to be a broad circle - for my 6 inch wingspan model aircraft I would need a 6 foot diameter well with adequate variable speed fan power from below. But it is not that tough. Cost should be peanuts. There is absolutely no reason why it can't be done. Spin testing is essential for every aircraft; forget the skydiving.

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Re: Indian Military Aviation - 21 Sept 2015

Postby Indranil » 17 Jan 2016 01:01

Hakim,

Building a vertical wind tunnel is not as easy as having a well with a fan at the bottom. In this case, the air won't be a smooth controlled airflow which is required for carrying out experiments. Like most wind tunnels, even vertical wind tunnels are designed as a loop where the air is made to circulate using one or more fans. One requires regions of convergence and divergence and some vanes to smooth out the flow and remove any turbulence. None, the less, it is not that difficult to build either. It will cost to 2-5 million dollars to build a good one, and about 2000-3000 hp motor(s) to drive the fans.

India as a country can easily spare that much for research if 10,000 crores can be spared every year for start ups.

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Re: Indian Military Aviation - 21 Sept 2015

Postby shiv » 17 Jan 2016 06:48

indranilroy wrote:Hakim,

Building a vertical wind tunnel is not as easy as having a well with a fan at the bottom. In this case, the air won't be a smooth controlled airflow which is required for carrying out experiments. Like most wind tunnels, even vertical wind tunnels are designed as a loop where the air is made to circulate using one or more fans. One requires regions of convergence and divergence and some vanes to smooth out the flow and remove any turbulence. None, the less, it is not that difficult to build either. It will cost to 2-5 million dollars to build a good one, and about 2000-3000 hp motor(s) to drive the fans.

India as a country can easily spare that much for research if 10,000 crores can be spared every year for start ups.

Frankly (and no one is expected to believe me) - I found it easy to achieve what I said - i.e have a fan blowing upwards and getting a model to spin in the airflow. The actual problems I encountered were something that did not seem insurmountable to me given space but I was not constrained by worries regarding turbulence. I was simply playing.

You know you can make a small ball (rolled up ball of aluminium kitchen foil) balance and dance on the steam coming out of your mummy's or wife's pressure cooker before the weight is put on it. And that does not even require any duct or streamlining. I will deliberately do that (and piss off my wife) and post a video. The principle of a vertical wind tunnel is pretty much the same.

Do you think that an engineering college cannot design a small one for Rs 1 lakh? My investment was Rs 3500 (pedestal fan lying on its back) and vertical duct made of card paper - Rs 40. Model glider Rs 100.

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Re: Indian Military Aviation - 21 Sept 2015

Postby shiv » 17 Jan 2016 08:01

It is dead easy to get a solid object to float in a stream of gas - although it is easier if the object is symmetrical. Here is a video that took me 15 minutes to set up and make since I made the last post - it is an animated gif that I posted on Twitter for convenience. Nothing special required. This is a 16 second clip of an rolled up ball of aluminium foil floating on air+steam stream from a pressure cooker.

https://twitter.com/bennedose/status/688563684017242112

I don't think a vertical wind tunnel is all that complicated - see the video posted by khedar

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Re: Indian Military Aviation - 21 Sept 2015

Postby Shreeman » 17 Jan 2016 10:18

sigh. all right.

...


Say,... Whats cooking, doc?

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Re: Indian Military Aviation - 21 Sept 2015

Postby Indranil » 17 Jan 2016 11:19

shiv wrote:It is dead easy to get a solid object to float in a stream of gas - although it is easier if the object is symmetrical. Here is a video that took me 15 minutes to set up and make since I made the last post - it is an animated gif that I posted on Twitter for convenience. Nothing special required. This is a 16 second clip of an rolled up ball of aluminium foil floating on air+steam stream from a pressure cooker.

https://twitter.com/bennedose/status/688563684017242112

I don't think a vertical wind tunnel is all that complicated - see the video posted by khedar

If you want to float something in a stream of air, what you suggest is fine. Similarly, one could add a duct to a table fan to get a "horizontal" wind tunnel as well. In fact, you might come across rudimentary wind tunnels built as university projects using industrial blowers. But that cannot be used to make deterministic safety critical calculations, wherein you are studying how a model's behaviour changes if you move its CG by 1% of its MAC, etc. If it were so, Indian scientist would have built one. But they cannot create a steady stream of air at 250 kmph required for designing of modern planes. If you do check out the prices of wind tunnels for entertainment (indoor sky diving), they range from 2-5 million. If it was that easy to build, they would not cost that much.

Langley's wind tunnel (the one in the video) is like this.
Image

The fan is actually at the top, and the shape of those walls are very carefully designed. If I remember correctly it is a 1500 HP, variable speed fan. Thw wind tunnel in France (I think it is at Onera) is of the same design. Wind tunnel 105 at Tsagi uses a different design, but it also uses circulation of air.

Image

At the same time, you are right. It is not THAT difficult. It requires a few crores to build and a few lacs to maintain, which till now India has denied its aero scientists.

I suggest you not to make the video with the pressure cooker. Nothing is worth an angry wife.

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Re: Indian Military Aviation - 21 Sept 2015

Postby shiv » 17 Jan 2016 11:47

indranilroy wrote:If you want to float something in a stream of air, what you suggest is fine. Similarly, one could add a duct to a table fan to get a "horizontal" wind tunnel as well. In fact, you might come across rudimentary wind tunnels built as university projects using industrial blowers. But that cannot be used to make deterministic safety critical calculations, wherein you are studying how a model's behaviour changes if you move its CG by 1% of its MAC, etc. If it were so, Indian scientist would have built one. But they cannot create a steady stream of air at 250 kmph required for designing of modern planes. If you do check out the prices of wind tunnels for entertainment (indoor sky diving)

No. For spin testing you DO NOT need a steady stream of air at 250 kmph. Which aircraft descends spinning at 250 kmph? Even a rock falling through the atmosphere stabilizes at about 180 kmph

You need to simulate a plane spinning and falling - and that is airflow from below as would occur once the plane stalls and goes into a spin. What is needed is the ability to control the speed of the airflow - manually so that a stably spinning aircraft model does not descend or ascend but appears to hover in the air allowing videography and observation of spin characteristics.

That is the difference between floating a ball in a steady stream and trying to make a spinning plane float on a column of air. When you introduce a model aircraft tail down into a vertical column of air it will may simply go nose down and recover from the spin. The basic requirement for that is to have a tunnel a few meters in diameter so that the spinning model can be tracked or else it will hit the wall of the chamber. You need a net at the bottom to catch it. In its most simple form the model plane is simply introduced into the airflow at some angle where it would be expected to spin and dropped in exactly like what is shown in the beginning of the video posted by Khedar.. An observer speeds up or slows down the airflow to make the plane "float".

The process of putting the model plane into the airflow is manual and the process needs to be videographed to record the behaviour. Of course and expensive facility can monitor a lot more parameters but a rudimentary one will tell one a lot about the spin characteristics of any scale model that one chooses to build and test.

And Googling will tell you nothing much about vertical wind tunnels for aircraft aerodynamics research. Google uncle talks mostly about recreational wind tunnels

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Re: Indian Military Aviation - 21 Sept 2015

Postby shiv » 17 Jan 2016 12:43


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Re: Indian Military Aviation - 21 Sept 2015

Postby shiv » 17 Jan 2016 12:44

Spin Tunnel Tests of a Fairchild A-10A Model
https://www.youtube.com/watch?v=VUKTBUY1RII

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Re: Indian Military Aviation - 21 Sept 2015

Postby shiv » 17 Jan 2016 12:51


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Re: Indian Military Aviation - 21 Sept 2015

Postby shiv » 17 Jan 2016 13:01

Vertical wind tunnels for aircraft spin testing have been made from the 1930s at least. I can't see what is so difficult, high tech or expensive about this. Do we have at least ONE in India or not? If not why not?

From http://citeseerx.ist.psu.edu/viewdoc/do ... 1&type=pdf
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shiv
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Re: Indian Military Aviation - 21 Sept 2015

Postby shiv » 17 Jan 2016 13:05

indranilroy wrote:If you do check out the prices of wind tunnels for entertainment (indoor sky diving), they range from 2-5 million. If it was that easy to build, they would not cost that much.

Are you seriously trying to compare human skydiving wind tunnels with all the safety features to keep humans alive along with higher air speeds with a 20 foot high vertical wind tunnel to test aircraft models that have been around for 80 years?

JTull
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Re: Indian Military Aviation - 21 Sept 2015

Postby JTull » 17 Jan 2016 13:56

I'm beginning to wonder if IJT problems have not been solved for so long due this lack of vertical wind tunnel in India?


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