Loss of the OTS 1 Satellite

OTS In Orbit - Artist's Impression

The OTS Satellite In Orbit – Artist’s Impression

This is a sorry tale of how four years’ work was destroyed in 54 seconds. Some say that the number thirteen is unlucky and on 13th September 1977, exactly 35 years ago today, this proved to be the case for me and the whole team that developed the OTS satellite. Here’s how things played out.

The European Space Agency’s Orbital Test Satellite (OTS) was one of the very first geostationary, 3-axis-stabilised Ku-Band communications satellites. It was developed as a test bed for a host of new European technologies and transmission techniques aimed at bringing regional TV and trunk telephony services to Europe. It was the forerunner of the highly successful ECS satellites which were subsequently operated and managed by EUTELSAT.

I spent four years working on different aspects of the OTS satellite, the communications transmission design and on the ground segment earth stations. For any interested readers with a technical bent you can check out details on the EXPERIENCE and PUBLICATIONS pages of this site.

In March 1977 I took on the role of designing, planning and implementing the in-orbit testing (IOT) of OTS. This was to be carried out from Telespazio’s Fucino earth station complex in the mountains east of Rome, Italy, and you can check out the Fucino earth station complex with the interactive Google Map on my related blog post here.

Telespazio's Fucino Site At The Time

Telespazio’s Fucino Site At The Time

I accepted the job on a Thursday and I was on a plane to Rome on the next Monday. So began what turned into two years of commuting between Amsterdam (home) and Rome. Seventeen trips varying in duration between one day and two months. Oh, and also fitting in visits to the USA, the UK and most western European countries overseeing different development contracts as well!

After six months’ work with a team of engineers and technicians we had six racks of test equipment installed and ready in the IOT test room, plus all the RF and calibration equipment installed in the two antenna cabins – a 3 metre and a 13 metre dish, the latter equipped with a number of 2kW high power Ku-Band TWTA transmitters. In addition, we had helicoptered-in the engineering model of the OTS satellite communications payload and installed it in a building at the very top of Monte Magnola, the highest (snow covered in winter) peak in the vicinity, some 20km distant from the earth station. We had checked out all our equipment and test procedures using this ‘local’ satellite payload. We were ready for launch of the bird itself!

The OTS 1 launch was to be from Cape Canaveral, Florida on a Delta 1 launcher, and our ESA launch team was well-ensconced there. ESA Operations in Darmstadt, Germany (ESOC) was the hub of all the satellite-related activity and all their telecommands and satellite telemetry was routed through our 13 metre Satellite Control and Test (SCTS) antenna at Fucino, via the equipment on the TTR room next to our IOT room.

On the night of the launch we were all gathered in the TTR and patched in to NASA’s audio network at the Cape launch site. I still have a copy of the tape of the countdown and the launch. A few snippets from the tape:
– Hydraulic systems on internal. (NASA control).
– Roger, copy. (ESOC control).
– All systems on internal.
– Roger, copy.
– We have permission to launch.
– Roger, copy.
– Commencing terminal count.
– Roger, copy.
– Ignition, liftoff. Liftoff time occurred at xxx(time) decimal 240.
– Roger, copy.
– The vehicle has cleared the Cape and the IP chart is moving along nicely.
– Roger, copy.
– We have lost the vehicle, the vehicle has been destroyed.
– Roger, copy.
– We confirm the vehicle has been destroyed, some 54 seconds after liftoff. Off the Cape, about 12 miles.
– Roger, copy.

NASA Camera Frame 1

NASA Camera Frame 1

NASA Camera Frame 2

NASA Camera Frame 2

NASA Camera Frame 3

NASA Camera Frame 3

And so the reporting went on. Absolutely deadpan with zero emotion. A very different scene in Fucino, though. I was just shell-shocked and stunned. The Italians, who included the Telespazio board directors, were unsure what they’d heard in a foreign language with an American accent. “Che cosa e successo? e vero? non e possibile!” etcetera, etcetera.
Here we were, ready and waiting to acquire and track the satellite, then switch on the communications payload in a 14 hour test sequence – and to hear this. Not a happy night; bit of a let-down, really. I took two weeks’ vacation after that, drove South and vegged out on the Isle of Capri.

It emerged later that there had been a horizontal crack in the solid propellant core of one of the strap-on boosters. This resulted in the core gases burning through the casing and these ignited the fuel in the main tank of the Delta 1 rocket’s first stage. You can see this clearly on the three sequential frames from NASA’s tracking camera.

The vehicle was still in the atmosphere when the explosion occurred, the fairing burst open and the OTS 1 satellite was literally blown apart by the wind. The solar panels fluttered down into the Atlantic Ocean. These, plus many other parts and debris – hydrazine fuel tanks, Ku-Band TWTA power amplifiers et al – were later recovered by divers. I’ve got a piece of one of the solar panels, set in a Perspex block, as shown here:

OTS 1 Solar Panel Fragment

OTS 1 Solar Panel Fragment

It lives on my desk.

Maybe the number thirteen is not so unlucky after all. I got a well-earned, two week holiday on the Isle of Capri and extra time in which to hone the IOT procedures prior to the successful launch of the spare satellite flight model, OTS 2, the following year. OTS 2 was a fantastic success and proved all the technology and techniques which fed in to ECS, MAROTS and the subsequent OLYMPUS Ka-Band satellite.

Photographs courtesy ESA.

10 comments on “Loss of the OTS 1 Satellite

  1. Ed Ashford on said:

    Hi Bob, As you know, I was at the launch site when the launch occurred. With the rest of the launch crew, I was inside the satellite control room until T=0, then we all rushed outside to watch the actual launch. 53 seconds later, when the launcher blew up, it felt like someone had punched me in the stomach. It seemed like years of effort had disappeared in seconds. Fortunately, I knew that there was the backup satellite, OTS-2, that could be prepared and launched later, which was the only thing that somewhat made up for the loss.

    What was even worse personally, however, was that my wife and (then just ) three year old son were in the viewing stands, and watched the disaster. My son, who had understand that it was “Papa’s rocket, with Papa’s satellite,” turned to his (Dutch) mother and asked “Waar is Papa nu?” (Where is Papa now?) Then he burst into tears, and nothing could console him until about about two hours later, when I could finally get back to the apartment where we were staying, and he realized after seeing me that I had not actually been destroyed in the explosion. Few adults remember things that happened when they were three years old, but that day is still, he says vivid in his mind.
    Ed Ashford

    • Satellite Spy on said:

      Hi Ed,
      I really appreciate you taking the time to comment on this. I hadn’t realised until today the personal impact this event had on you and your family.
      In my perception at the time, you were the senior, experienced, dynamic Programme Manager who overcame so many obstacles to making OTS become a reality and I was just a small cog in your bigger wheel.
      Thank you for sharing your insights.
      Cheers, Bob

    • Christine Dowsett on said:

      My father, Jim Weaver (James John), worked at ESTEC in Noordwijk on the MAROTS project in the early ’70s. He was in his late 40s. Sadly he died in 1975, when I was a mere 16, so he never saw it through. I do still, however, have my scale model of the satellite albeit missing a wing.
      My brother is doing some research for the grandchildren and I was wondering if you by any chance remember him? Or if anyone else does?

  2. Walter Thiebaut on said:

    Walter Thiebaut
    Walter Thiebaut
    Visiting Professor Space Law and Policy at KULeuven, Ere-voorzitter Vlamingen in de Wereld

    I was present. As junior ESA Washington Office representative I was in charge of the VIP’s invited for the launch.Among them Mr Luns, Secretary-General of Nato, Fernand Spaak, Head of the European Community Office in DC, Ambassador Telesphore Yaguibo of then Uppor Volta etc.
    For ESA, René Collette, Ed Ashford,, Wilf Mellors, head of ESA’s Washington Office and a lot of good ESA friends.
    Walter Thiebaut

    • Satellite Spy on said:

      Very kind of you to share this information, Walter. Thank you.

      Ed Ashford – enough said. Mr ‘Make it Happen”. He’s any major project’s ‘Go to Guy’ to achieve results on time and on budget, yet in the nicest possible way.

      I knew Rene Collette very well – an exceptional, affable individual who became ESA’s Director of Communications Satellites Programmes. What an incisive mind and a nice person too.

      OK, we all know my old friend and boss Giulliano Berretta became DG of EUTELSAT. I’m still in touch with Simon Dinwiddy (Galileo project) and Leif Lundquist, but what became of some of the other outstanding team members, such as Mario Lopriore, Pierre Bartholome (ex-NATO SHAPE Technical Centre), Cliff Hughes, Dr Bob Harris, Cesar Moens et al?

      Again, thank you => https://www.satellitespy.net/tks

      • Simon E. Dinwiddy on said:

        I have one of those lumps of plastic with a bit of OTS1 solar array!

        We visited Pierre Bartholome in Belgium last year. He is still active, writing an essay on space and mankind. Bob Harris still lives in the Netherlands and we usually see him when we visit our son, who has also settled there.

        The story I heard was that there was a void (air bubble) in the solid fuel of the strap-on booster rockets, so that the rocket fuel did not burn evenly but the fire jumped over the void, burnt through the booster casing, melted the body of the main rocket and set its fuel on fire.

        We lost ECS3 as well. I recall singing a lament to it at the ECS Contract Completion Party in Redu.

        Artemis launch was the nearest that a failure could come to success. Its orbit after launch was way too low but incredibly skilful work by teams in ESTEC, Noordwijk, ESOC, Darmstadt, and Alenia Spazio in Rome, rescued the mission, used the experimental electric thrusters to raise the orbit, and allowed lots of fascinating experiments to proceed, including data return from Envisat via data-relay link and the precursor Galileo transmissions of EGNOS.

        Great days!

        • Satellite Spy on said:

          Wow – Simon Dinwiddy – my old friend and ex-boss!
          Lovely to hear from you as it’s a while since we’ve been in touch.
          A very nice surprise to see Bob’s comment too, as it came completely out-of-the-blue.

          You’re right about the cause of the launcher explosion. It was exactly that defect in the solid propellant of the strap-on booster that caused the main rocket fuel tank to explode, some 54 seconds after lift-off.
          Please pass on my regards and best wishes to both Pierre Bartholome and Bob Harris when you next get a chance. I would be very interested to read Pierre’s essay on space and mankind and would be more than happy to promote it, both via this website and my other publishing affiliations, should he so wish.

          I caught up with Ed Ashford a couple of years ago at the AIAA ICSSC 2015 Conference, where he received a major award for his work on satellite communications. Details are here: https://www.satellitespy.net/blog/conferences-exhibitions/satcom-september-icssc-2015-1913/

          All the very best my friend,
          Bob Gough

  3. Colin Wearmouth on said:

    Hi Bob,
    Just read your interesting account of the Ots 1 launch failure. It brings back painful memories. I was the Prime Contractor Project Manager at the time and watched the launch from the Firing Room along with Brian Stockwell and Roy Gibson as I recall. It was a bit confusing watching the screen because it was close in time to the staging of the Castors so some thought that was what had happened at first.

    Ed Ashford’s son was not the only one in tears – so were some of our launch crew.

    Don’t know if we ever met but I was with the OTS/ECS programme for many years – fortunately through the successes too.


    • Satellite Spy on said:

      Hi Colin,
      I certainly do remember you, and we may have met briefly at the OTS Critical Design Review. Brian Stockwell I do know.

      ECS was a great success (a good prime contractor, see!). I was part of the team that conducted the negotiations to transfer the ECS satellites from ESA across to what was then Interim EUTELSAT. From a contractual point of view I was in a nutcracker – identical specifications had been used in the contractor’s Incentive Payments Scheme and in the ESA/EUTELSAT contract.
      Payments of $millions hung on the measurement accuracy of those in-orbit test results – i.e. in my lap!
      It all worked out fine in the end though.

      Really nice to touch base again after all this time, and I appreciate you taking the time to comment.

      Kind regards,

  4. Bob dinwddy on said:

    Nice article Bob ! It’s lovely to see all the names in the comments too, all very familiar to the ear 🙂 the fragment on Dad’s desk is a slightly different shape but none the less very memorable. I also recall a press-release photo showing the aforementioned launch fault: a clear puff of brown smoke set off against the white solid-fuel booster rockets around the base of the first stage.
    Perhaps also worth a mention is the phoenix from the ashes of this mishap:
    ECS – European Communications Satellite.

    kind regards, Bob Dinwiddy

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