“A couple of days ago I was perusing my Second Book that I am still writing, . This book is to cover my life from 1998 to the ‘present’, in a future tense (!!! ???)
In it I had written a few words about my friend Groupie Das, around 2005, which I now think may be appropriate to reproduce here in the light of the Marut debate that is on going.”
“Much later in 1969, after I had immigrated to the USA, I learnt that my very good friend Das died in an aircraft crash in Bangalore, on 10 Jan. 1970, while test flying an HF-24-1R at HAL, Bangalore. This aircraft had a GTRE designed Orpheus Engine Partial Reheat System (1R), which was under development at that time. I knew him very well and we were very close to each other. While in the USA, I learnt to my very great horror, and with great sadness, that Das had died in an aircraft accident, which, it was alleged, perhaps was not fully and properly investigated. I have heard it being said that the cause of this accident was wrongly attributed to ‘pilot error’. It is not easy to believe this was ‘pilot error’ in Das’s case. He was a super test pilot, and so it is not very credible that the ‘court of inquiry’ that was constituted could have found this to be so. I have not had any access to the C of I findings nor has anyone shared its details with me. It is alleged that during his take off roll at the HAL airfield, he did not close and lock the canopy. It is stated that Groupie Das was used to keeping the canopy partially open during his taxying to the take off point. He did this supposedly to feel more comfortable with getting some fresh air into the cockpit. There are a few who allege that Das had not locked the clamshell canopy before he started his take off roll. By not doing so it is possible that the canopy opened a few degrees as he was a few seconds into his take off run. Such a partially open canopy should have ejected if Das had tried to eject it. I say he definitely must have done so. In the canopy system design there was a weak link designed to ‘fail’ and release the canopy when the release lever (canopy unlock) was operated. It was later found, it is alleged, that the ‘weak link’ that was designed to fail did not fail (snap), as it should have, so the canopy did not separate from the aircraft. If the canopy was open a few degrees during the take-off run there would obviously have been some extra aerodynamic drag on the aircraft. Then, it has also been alleged that Das operated his ejection seat handle to fire his zero-zero ejection seat. The seat did not eject!. This was explained in a way that since the canopy did not separate from the aircraft the seat could not also have ejected, because of a safety pin that prevented the ejection seat from being armed due to the canopy non-separation. Another, in my opinion, outlandish theory that I also heard was about a failure of the starboard reheat engine during take off due to the canopy being partially open during his take-off run., supposedly creating unwanted air turbulence at the air intake. I personally discount this completely because the air intake position is far enough forward on the fuselage not to be affected by a partially open canopy during the low speeds of the take-off run. Was all this attributable to pilot error?! It is also my understanding that there were some very senior Air Force Officers in the Air Traffic Control Tower watching this whole episode. I have heard it said that some of them felt that the findings of the Court of Inquiry did not reflect the true realities of what actually happened. It is very difficult for me, at this time, to suggest that these people did not offer to give their ‘correct’ evidence of what actually happened, if they indeed were watching all this happen in real time!!
To me, this is a tragic loss of a very good pilot and a brilliant colleague. A tribute to his greatness and as a memorial to a very very dear friend”
Marutfans 
From Groupie Chakko by email
Dear Kapil, and Friends,
I really do admire your sense of recall of many details of the HF24 that I have totally forgotten, even though I was the STO on the IAF HF24 Project Team stationed at HAL. This Unit was commanded by the late AM Zoot Zaheer. I left the Unit in 1967 to command the No.3 BRD in Chandigarh. I came back to HAL the next year to form the Manuals and Publications Group, setting it up to write the Manuals for the HF and other HAL aircraft. There were a few who did not want to see me associated with the Design Group. But that is history, and I moved on.
I heard of Groupie Das’ sad passing when I was in America. During my later visits to India I heard of some of the circumstances of Dasu’s accident. Strangely the ones I talked with, even Senior iAF Ofiicers, did not ever mention to me that the ‘Canopy had opened to an upright position’ on the HF during the take-off roll. As a matter if fact I am seeing this for the very first time in Kapils recounting and recall of events, in reply to Dara’s blog.
There is no question of my disputing many of those details of Kapil’s recall. And especially when I now realise that the canopy was opened to the vertical position on the take off roll and continued to be attched to the HF, it is to my mind a doomed situation for the pilot.
The intimate details of the canopy design escape my memory at this time. However it is my belief that in that vertical position of the canopy it should definitely have seperated from the aircarft. Its non-separation could only have been due to the failure of the shear ‘weak links’ in the canopy release system. If the canopy had separated from the aircraft in the designed fashion, the zero-zero ejection seat would also have ejected as designed. I cannot believe it that it is only now that I am made more aware of some of the actual details. I was also told at that time, that somehow the seat-ejection cartridge was ‘wrongly’ installed, so that also by itself could have prevented Dasu’s safe ejection. I regret that I was gullible enough to have believed some of these fables from very Senior Officers who were allegedly ‘real-time’ eye witnesses to the tragic events of that day.
Any way, my dear friend Kapil, please allow me to continue to believe that Dasu being who he was, was really a Super Test Pilot. And having interacted very closely with him since 1952 with the Ouragans and in the Aircraft Selection Team under ACM Lal, with the Mysteres, and the Gnats and the Jet Packets, and the HFs etc, that I will continue, in my admiration of the man, to hold him in greater esteem than many other people may do. Obviously this is very much my own very personal relationship, which in no way takes anything away from the many others who are even today associated with aircraft design and test flying them today in the year 2010.
But whatever else be said, I have always known there are so many “weak links” in our much vaunted Air Force, that even as the “fourth largest air force ” in the world, we are still so dependent on, and at the mercy of, foreign technology transfers.
We have ‘manufactured’ and ‘overhauled’ high powered piston engines, thousands of turbo-prop engines, jet engines, and aircarft since 1944, and yet even today in 2010, I cannot point to even one well designed indigenous piston or jet engine, even of mimimal horse-power or thrust in full production for our use. So I say today, without any fear whatsoever, “Shame on all of US”. I could even go a bit further and say like Dreyfus did in his time, “J’accuse”.! There may be some Emile Zolas too in our midst, then to help us.!!!
But all this may really be moot at this time since the Chinese have already ‘encircled’ us with their deep sea ports in Gwadar, Hambantota, Chittagong, in Sitwe, in the Cocos. They have also built their major rail and road networks from Beijing to Lhasa and those 37 military airfields in Tibet, all to “promote friendly tourism with India, a burgeoning Super Power “!!. And with the help of Pakistan and many of the embedded Commies, Maoists and Naxals and Lingiustic Quislings in our midst, they do not really have anything to worry about, do they?.!!!
Any way, all I will say again, is that we really lost a beautiful aircraft that could have been a super fighter if we had the done the right things at the right time, and worked as a team instead of being at each others throats and avoided being our narcissistic selves. And in tribute to those who paid that ultimate price, let us pray God together…
“””They shall not grow old, as we that are left grow old.
Age shall not weary them, nor the years condemn.
At the going down of the sun, and in the morning,
We will remember Them.””””
With my regards,
Jacob Chakko.
Here are three additional comments I needed to add as mentioned above: –
Gp Capt Jacob Chakko has expressed his extreme but understandable ire at the suggestion that Groupie Das could have made a mistake of not locking the canopy. Unfortunately, this seems to have been the case.
I should clarify here that the thrusters to eject the canopy could not work if the canopy was even partially open. They needed the canopy in contact to push it off. There was no way Groupie Das could have ejected the canopy if it did not fly off. Anyway, it had opened to upright position and he must have hoped that it would fly off. It did not.
Gp Capt Chakko’s assumption that Groupie Das could never make a mistake is unjustified. Absolutely no one is infallible at all times. More than one person confirmed at HAL that in fact he did keep the canopy unlocked and held it up slightly to get some ventilation during taxiing. There is little doubt that the clamshell canopy used for the first time on the HF-24 was unlocked and opened up to vertical position as speed built up.
Since its description is quite long, my personal part in attending to the aftermath of the sad accident is submitted as a separate entry to this blog.
Sir, I had joined A&ATU as its OC on my return from Egypt just a few days earlier when I learnt of Groupie Das’ accident. There could well be some truth in the fact that the canopy was not locked. The reasons why I think this will take more space than just a comment here. I will write them down as soon as possible and ask the blog’s owner to put them up.