AV Skydives with Felix Baumgartner, Part 1When Felix Baumgartner jumped from the edge of space, Riedel Communications was handling comm lines, video, and radio links for the whole project. 12/06/2012 7:47 AM Eastern
AV Skydives with Felix Baumgartner, Part 1
Dec 6, 2012 12:47 PM, With Bennett Liles
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When Felix Baumgartner jumped from the edge of space, Riedel Communications was handling comm lines, video, and radio links for the whole project. Matthias Liester of Reidel is here to give us a fascinating look behind the scenes at the tech setup for the world’s only supersonic skydive, coming up right now on the SVC Podcast.
SVC: Matthias, it’s great to have you on the SVC Podcast from Riedel, coming to us all the way from Germany today, and as we’re recording this you’ve just gotten back home and your team is still unpacking gear from the big Red Bull Stratos jump with Felix Baumgartner leaping from a balloon at around 128,000ft. over Roswell, N.M. They called in Riedel to handle a very big job with this. So let’s rewind a little bit. When you got the call from the Red Bull Stratos people, what did the project team need from Riedel?
Matthias Liester: Yeah, the first call I got basically that was in 2009 was for basic communication for the event crew and mission control, so all I could think of was probably a size of 30 intercom panels and a few radios, up to 100 radios, with potentially eight radio channels. That was my idea so far before I got to really meet the whole team and understood what’s truly necessary. [Timestamp: 1:46]
They had a lot of different technical requirements, but I was curious about the cameras carried on the capsule. They had cameras everywhere. Were those specially made cameras?
No, the cameras were actually not special. It’s the same camera type—the LMP HD1200. It’s the same camera type that we already used for the Red Bull Air Races years ago, but of course what we needed to do is prove that these kind of cameras will survive in this environment that we were going to fly issue and that was a step that we needed to go first. [Timestamp: 2:21]
I understand that you had a control system and that you could switch back and forth between the cameras that were connected to the downlink. So how did you control the cameras and record the video from each one?
Yeah, that actually was a special developed system from our engineers here in Wuppertal. What we did is we had a 2-channel digital radio system capable of talking to a controller that was inside the capsule and this controller had the capabilities of start, stop, recording, do the color balance of the cameras, and such, and all that remote controlled in mission control. [Timestamp: 3:00]
OK and they had cameras and sound, and this is, of course, a pretty hostile environment and the transmission link was quite a distance since the capsule I think floated some 50 miles or so away. What was the transmission power used to cover the distance?
Yeah, the power for transmitters actually wasn’t that high. It was only 5W COFDM RF output, so the benefit that we used was a very good tracking antenna on the ground and high gain antennas under the capsule. [Timestamp: 3:34]
So what you don’t have in the air you make up for on the ground with the size and power of pulling it all in.
Where was the downlink on the ground? Was the recording done in remote trucks or was it done in mission control or how did all that work?
Actually we had two downlinks or two receive sites on the ground. One was beside mission control. It was near our office. The second one was out in the field where the optical tracking trucks were placed and both of these ground RX sites were capable of receiving all of the video signals. One was fed into a MediorNet system directly on the compound and the other one was used via a point-to-point link and also then put into a MediorNet system. What we did then is used ASI switch to determine what is the best signal we currently have and then put it into our decoders for providing that signal from mission control in the OB truck and that OB truck was obviously the point where the signals were recorded afterwards. [Timestamp: 4:24]
AV Skydives with Felix Baumgartner, Part 1
Dec 6, 2012 12:47 PM, With Bennett Liles
You compared the signal to get the best one.
That was an automatic system. An ASI, which is on that ASI level determine what the best signal is or if they’re corrupted within these ASI streams. [Timestamp: 4:57]
OK, and automatically switches to the best signal.
Exactly, seamlessly. Yeah.
When you got the call and you knew what the project was, obviously no big surprise but there was a lot of planning that went into this. When you got to the mission control site, how long did it take to get the whole system set up?
Yeah, the whole setup takes us about 10 days prior to launch day, but that includes also the connection to the OB truck, the connection to the media sites. There’s a BBC office in place that needs to get the signals in edit room where the signals are during the mission are already edited for postproduction. So that whole setup took us about 10 days for really being able to start the mission. [Timestamp: 5:43]
And there’s a huge amount of coordination that had to happen because you’ve got to know exactly what everybody is going to be doing and what they’re going to need and that’s a lot of phone calls and conferences and maybe some changes along the way after the first few rehearsals and simulations.
Yeah, actually since this mission was already for us a kind of development all over and from the first point on there have been changes; there have been developments. Nevertheless, of course, before the first manned launch, we had unmanned flights where we already could experience what necessary changes we need to do to make the whole system match everybody’s needs. [Timestamp: 6:24]
And since the altitude where this gear was going was almost 130,000ft. you’re talking about some extreme temperature changes and that had to be a factor with some of the electronic gear onboard. So did you have to take any special precautions to deal with the very low temperatures?
Yes and no. It was definitely extremely hostile environment nevertheless, [but] the cold itself wasn’t really a factor. You need to remember that though you have the extreme cold, there’s no way for the heat of electrical equipment to go away, so we had two problems. One was the external cold on the other side, infrared heating plus not having the ability for the equipment to vapor its heat off. So what we had is there is a special keg built into the top of the capsule above the pressure sphere Felix is sitting in. Within this pressured housing we had all the electronics components together. [At] the end of the day what came out was that we needed to provide external cooling for that housing. Just by the amount of electrical equipment inside it was generating so much heat that we needed to cool it in addition. [Timestamp: 7:42]
Yeah, I guess when you get up that high, anything in the shade is going to be really cold and anything in the sunlight is going to fry like a turkey.
Exactly, yeah. That’s the reason why most of the capsule is painted in a light gray. The camera housings that were exposed to the outside were painted white from the outside and black on the insides. So we had the perfect or best conditions of reflecting the outside heat and absorbing the inside heat and take these to the housings. [Timestamp: 8:13]
OK you have everything coming from the capsule itself and once the jump was made then things got even more complex because you had a helmet mic and some cameras on Felix as well. That’s an extra communication link that you have. How did the helmet mic transmit to the ground and did it relay through the capsule or did it go straight in the ground?
The helmet microphone actually had two paths: One path and that was to … while Felix was sitting in the capsule there were two redundant radios, digital encrypted radios, communicating to mission control and of course since the capsule had very sophisticated battery system we could use high power to transmit back to mission control. On the other hand, of course, at the point where Felix was jumping he didn’t have these capabilities of using really high powered radios, so at this point we were using also our remote site and an antenna mounted on the tracking trucks, on the optical trucks, that were tracking Felix. With this antenna we could communicate directly to Felix and that was relayed through one RF tower out in the field called the Caprock, (NM) Tower, the TV’s tower station where we placed another digital repeater to repeat Felix signal back to mission control. [Timestamp: 9:35]
And Riedel was handling the transmission. Did the radios have to be specially made for this?
No, the radios were not special made. These were third-party radios. We did some minor changes on the radios, but yeah basically these were radios that you could usually buy also. [Timestamp: 9:53]
And with anything that flies, weight is always a critical factor. How critical was the weight of the onboard sound and video system? Were you given a certain weight figure for all your gear that you had to figure out how to stay below?
Of course there was a weight limit and that was true for the whole so called payload system. So the payload system included everything—all the cameras, the recorders, the video router that was installed to switch the several camera signals onto the three video downlinks. What unfortunately happened is that we exceeded this limit together with the other parties involved for this payload system. Nevertheless when the whole capsule went together—and that was a new experience for the whole team—when the capsule went together, we found out that the overall weight limit is still not exceeded, so we were all lucky that we made it. [Timestamp: 10:44]
Alright, well, I know that it was exciting to work on and to be a part of that big event and I congratulate Riedel for doing a great job. In part two we’ll get into how things happened on the ground and it was a whole lot more than what was in the air. Matthais Leister from Riedel thanks for being with us and we’ll see you again in part two.
Thank you very much.