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Tom Hoffman

17 February 2023

Erik M. Conway,

Interviewer

Q: This is Erik Conway. I’m talking to Tom Hoffman today about his tenure as project manager

for the InSight Discovery program mission.

So, Tom, we’ve talked about your time on GRAIL just a few weeks ago, so tell me about 

your transition onto the InSight mission.

Hoffman: Okay. That’s a good transition question. [laughs] So I was actually on the GRAIL

mission and we were getting ready to launch in 2011. A few months before we launched, I got 

selected as the project manager on a Step 1 proposal that was at that time called GEMS, which 

eventually turned into InSight. Right about the time that we were getting ready to launch is when 

it got selected to go into Step 2 of the competitive process. So pretty much right after launch, I 

supported the mission operations for GRAIL, and in parallel with that, I supported getting the 

proposal turned in for the Step 2 effort on InSight. Then we ultimately ended up getting selected 

in—I can’t remember the exact date. It was actually Bruce’s birthday in August, the 20th , of 

2012. So about a year later (from the GRAIL launch), we were selected and I started full-time as 

the project manager, Bruce Banerdt as the PI.

Q: So you were on InSight almost from the beginning.
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Hoffman: Yes, almost from the beginning, although the beginning is a pretty fungible thing, I 

think. If you talk to Bruce, he would probably say he’s been working on InSight for decades—

Q: Oh, he did.

Hoffman: —or some version of that.

Q: He did.

Hoffman: And that’s true. That’s definitely true, yeah.

Q: I was just going to say we spent the first hour of our two hours so far talking about all of the 

previous efforts before InSight that led up to it. Yeah, he worked on it—a lot of these scientists 

do. They spend their whole lives trying to get these missions.

Hoffman: Yeah, being a scientist is a tough gig. A lot of them spend decades and don’t actually

ever end up getting their main project selected, so, you know, it’s lucky for Bruce that he finally 

got it, but it did take him most of his career to get there.

Q: It’s challenging and impressive that there are people with that sort of perseverance, especially 

since they know the odds that maybe a third of people who spend their time doing that actually

succeed, maybe less than that.
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Hoffman: Yeah, I bet it’s actually less than that. Our deputy PI on InSight, Sue Smrekar, 

similarly, she’s really a Venus scientist and she finally got VERITAS selected in the last 

Discovery call. She’d been working on that, similarly, for decades. It came in very close a couple 

of times, but just wasn’t quite selected until this last round.

Q: Yeah, and then it was delayed.

Hoffman: Yes. [laughter] So it’s a tough business.

Q: It’s a tough business is right.

So my next question was, what was the state of the project when you became project 

manager? But the answer to that is you came in almost towards the beginning in the proposal

process, so that’s not quite a fair question.

Hoffman: Yeah, I had a chance to mold the—within the constraints of the Discovery program, 

which is cost-capped and a fixed launch date and there’s a bunch of constraints on it, but within 

those constraints, I was able to come up with the plan that would work, so I only have myself to 

blame at some level for the planning, although the partners and everything like that was selected 

in Step 1, and, in fact, had been selected in previous instantiations of the proposal, so I came in 

with those already having been selected by Bruce.
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Q: So the major selections are already done, but there still have to be a whole series of other 

decisions about—I know one of the classic problems at JPL is whether to have JPL make a thing 

or to buy it, so you still had to do those kinds of things.

Hoffman: Yeah, we actually already had selected—before I came on, Lockheed Martin had 

already been selected as the prime spacecraft contractor, largely because of their having built the 

Phoenix, which was originally the Mars ’01 lander, but since we were going to be using pretty 

much an identical system and that was the right kind of system for us, it made a lot of sense to 

have already selected Lockheed Martin to do that work.

Most of the major partners were already selected at the beginning of Step 1, but we did 

have some additional selections to be made. For example, we did not have a solid solution for a 

temperature, wind, pressure sensor system. There was one that was in the proposal, but once we 

actually got selected and started digging into it a little bit more, it didn’t really make a lot of 

sense, so they did have to make a change within about the first year of how we were going to do 

that. Those particular measurements were highly important for the main science experiment on 

InSight, which was the seismometer, because the seismometers, generally just seismometers in 

general, are very good at detecting everything, including temperature changes, small vibrations, 

you name it. On Mars, because we can’t put it in a vault and basically completely encase it in a 

humidity-, temperature-, climate-controlled environment, we’re sitting on the surface of another 

planet, it was particularly good at detecting everything other than Marsquakes, if you weren’t 

careful. So we needed to have a good system to be able to know what the temperature was, know 

when it’s windy or not windy, know when there’s pressure changes so that we could then use 

that data to de-corelate those influences when we got the actual seismic data. In the end, it was 
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an important aspect of the experiment to have a solid solution for temperature, wind, and 

pressure.

Q: And where did you get that from?

Hoffman: We ended up getting an instrument that we called TWINS, which stood for 

Temperature, Wind for InSight, TWINS. That was TWINS. That was done by CAB [Centro de 

Astrobiologia], which is in Madrid or near Madrid. It’s the same folks that developed that for the 

MSL and then also followed on with Perseverance. I think they call that REMS [Rover 

Environmental Monitoring Station]. That was the same set of folks. And that solved two of the 

three issues.

The third was a pressure sensor, and that one took a little bit more effort to determine 

what the right solution was, and then it definitely took more effort to get it delivered. We 

actually got that from a small company up in the Sierra foothills, which I don’t remember the 

name of the company, but it’s basically a really good pressure sensor in the end, but it took a lot 

of extra effort to get it delivered.

Q: Hmm. You’d think a pressure sensor wouldn’t be that hard, but I guess for Mars, everything’s 

hard.

Hoffman: Yeah, and that was exactly the issue, because normally what you want, what pressure 

sensors on the Earth do is they measure the pressure, which makes sense, right? That’s what a 

pressure sensor does. For our pressure sensor to be useful on Mars, not only did we have to, like, 
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recalibrate it for the Martian atmosphere, which is 1/100th of the pressure of Earth, but what we 

really cared about was a very quick measurement of the delta pressure. We didn’t actually care 

what the absolute pressure was at all. We just cared about how quickly the pressure was 

changing, because pressure changes is actually what caused noise within the seismometer. So we 

were using the pressure sensor in a way that nobody on Earth uses it or cares about it, because

nobody cares if you have a 1/100th of a percentage change in your pressure on Earth, because

nobody can tell, but a seismometer can. So we were using a pressure sensor in a non-standard 

way, for sure.

Q: That makes sense. On Earth, nobody would care about a pressure change that small. Certainly 

meteorology doesn’t. It would be irrelevant.

Hoffman: Yeah, and not on, like, you know, sub-second timing either, because a hurricane’s not 

going to hit you. It’s going to take days, not seconds.

Q: Not seconds. Right. Fascinating.

Hoffman: As JPL does, we used something in a completely different way than it normally is

[used], but it ended up working out fine. It just took a lot of effort because, again, we were trying 

to use something in a very non-standard approach.

Q: As you were setting up InSight, what did you think your chief challenges were going to be? 

Then we can talk about what were they actually, but what did you think they would be?
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Hoffman: Well, I thought that the big challenges were going to be trying to get the spacecraft

delivered on cost from Lockheed Martin, because they had relatively recently, I’ll say, built the 

Phoenix spacecraft, but, from what I know about it secondhand, it had a reasonable cost growth, 

and we were a cost-capped mission, as was Phoenix. I couldn’t really afford a large cost growth 

there, so my number one concern was are we going to be able to get that delivered on cost. I had 

had a lot of history with Lockheed Martin, so I wasn’t overly concerned, and, anyway, they were 

going to be providing us the best value. It was just a question of, had we really done a good

enough estimate to build a Mars delivery system in the form of a spacecraft, just because that’s 

one area where you traditionally had a fair amount of growth in cost with Mars missions. So that 

was probably my number one concern going into it.

As we got a little bit further into it, I had some concerns about things like the pressure 

sensor changes that we had made to the baseline within the first year or so, but in retrospect, I 

can’t say, boy, I really thought a lot about the payloads, because I didn’t, and that’s where we did 

end up with problems. The reason I largely didn’t think about that is during the proposal phase of 

Step 2, it seemed like they were well on their way and well ahead of the spacecraft both in terms 

of maturity and in terms of sort of their test program and already had some prototype units, so 

from that standpoint, that seemed like it was in good shape.

I’ll say the other reason why I was a little bit concerned about the spacecraft is even 

though we were getting good heritage from the Phoenix mission, most of the—in fact, all of the 

avionics basically were changing. We had to move from a RAD 6000-based computer system, 

which is more like a nineties-type technology basis for the avionics. We were moving to the 

RAD750, which is more the early 2000s, 2010s-type technology basis, and that meant that we 
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had to have a new set of software, transition all the algorithms to new software, and just making 

sure that in that transition we didn’t make a mistake, which we didn’t, but trying to make sure we 

didn’t make a mistake there was an important thing for us. That was part of the focus and one of 

the reasons why I was more focused initially on the spacecraft. Plus, because we were getting 

most of the instruments from foreign contributors, foreign partners, there was very little chance 

for cost growth there, because they’re basically coming for free.

Q: But even free instruments don’t necessarily turn out to be free.

Hoffman: Oh, there’s no free lunch. [laughter] Yeah, there’s no free lunch. But even with the 

different problems that we had, that we started getting closer to the original launch date, we 

didn’t spend huge amounts of money, I’ll say. We maybe spent a few tens of millions of dollars, 

which is not a small amount of money, but in comparison to the spacecraft, which was a couple 

of hundred million dollars, it’s still a relatively small portion of the overall cost of the mission.

Q: Right. What you say makes sense to me simply because, as you said, we’d built the lander 

before, the instruments Bruce would swear were pretty mature going in, and so it really sounds to 

me, from all the other interviews I’ve done, that people were pretty surprised when it turned out 

that SEIS was not really buildable by its original contractor and so forth.

Hoffman: Yeah, and I can kind of get into that now. There were a few contributing factors when 

I’ve looked back on how did we get there, when we couldn’t get SEIS delivered on time for the 

2016 launch opportunity. There were a few different things that contributed to that. Some of 
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them were technical, some of them were geopolitical—maybe I’ll characterize it that way—and 

some of them were just sort of an expectation.

So the technical aspects came in a few different ways, and probably one of the more 

important ones was initially, when we had these prototypes that were working around the time of 

the proposal, the form factor was different than what we actually were going to fly. I don’t think 

anybody, including the people building it, truly appreciated how difficult it would be to shrink 

those just a little bit. We weren’t shrinking them by a factor of an order of magnitude. We were 

only shrinking them maybe 25 percent, but that ended up being a significant change in the 

overall design. And the reason that we had to do that is we ended up inheriting the 2001 arm 

from Mars 2001, which was going to originally be used by Phoenix. Phoenix replaced that with a 

different kind of arm, because that particular arm on 2001, very good for, like, placing stuff, 

which is what we had to do on InSight, but not good at digging. It wasn’t strong enough for 

digging. So Phoenix was digging with a different arm.

So, anyway, we got the 2001 arm as part of the proposal, and to build a brand-new arm 

would have cost tens of millions of dollars, so we really needed to use that arm, even if we had to 

refurbish it some, which we did have to do. But because of the constraints of how much that arm 

could lift, we needed to go through an effort relatively early in the project of shrinking the mass 

of the SEIS, and in the process of shrinking the mass of the SEIS, that’s where I think some of 

the technical difficulties that nobody fully appreciated got partially baked in. So they had to go 

through and do a redesign of their very broadband sensor, the VBB, and kind of shrink all the 

internal aspects and the overall size of the sphere. So that sort of kicked off a design effort, but 

that was characterized to, I think, pretty much everybody, as, oh, it’s just simply shrinking the 

size of things a little bit. So, honestly, I think that was the bigger change than anybody fully 
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appreciated at the time, and I’m not sure people fully appreciate even today. But I think that was 

part of the root of the problems, but certainly not the only problem.

Q: Nobody’s mentioned that one to me. Most of the stories have been about the cleanliness 

issues and the vacuum issues, but no one’s mentioned an early effort to shrink it by a quarter.

Hoffman: Yeah, and a quarter is a relative—I think it was actually—yeah, it was something on 

that ballpark, roughly. I think there originally may be 12-ish kilograms. We needed to get them 

under 10 kilograms, and we were trying to get them to 8, so, you know, it’s a relatively close 

number.

Q: Interesting.

Hoffman: But that did cause them to have to lightweight a fair amount of things, which is 

partially the reason why we had too thin of a sphere that collapsed at one point, but, yeah.

Q: Yeah, that would make sense, and how the buckling analysis didn’t get done and etc.

Hoffman: Yeah.

Q: So it all kind of snowballed.
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Hoffman: Yeah. Have you, by the way, on your list of people to talk to, are you talking to Jeff 

Umland at all?

Q: Jeff Umland? No.

Hoffman: Umland, U-m-l-a-n-d. You might want to talk to Jeff. He’s a fellow at JPL, but he was 

our chief mechanical engineer for InSight, and he definitely was heavily involved in the 

mechanical aspects of both the spacecraft but more interestingly and more importantly, the SEIS. 

If you’re interested in pulling the thread on the mechanical aspects, he can definitely provide 

really valuable insight, I think—unintended.

Q: Okay, great, great. I think that would be interesting. I’ve talked to Ken Hurst already, but, of 

course, he’s still more scientist than engineer, so I need to talk to one of the mechanical 

engineers.

So let’s see. On the spacecraft side of things, what was your development experience? As 

you say, I know Phoenix had issues, although a lot of theirs were around the landing radar.

Hoffman: Right.

Q: What were yours?

Hoffman: Yes, yes. So we did learn a fair amount from the different issues that Phoenix had, so 

part of the concern was the landing radar. We did end up flying the same landing radar as 
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Phoenix. Phoenix had gone through and done like a hot-fire test, a bunch of helicopter tests to 

verify the whole landing system, and we definitely took advantage of that program.

Actually, we took the unit that had gone through the helicopter testing as our radar unit, 

because, again, within our cost constraints, a new radar system is anywhere from 50 to 100 

million dollars, and I didn’t have that much total UFE to begin with, and we had planned to 

always use this particular radar system. There was not a lot of expense associated with that from 

the baseline estimate.

So we did end up using the unit, essentially the flight spare for Phoenix, which had gone 

through this helicopter testing. We did refurbishment on it. We pulled it apart, we looked at 

everything. In the end, we replaced a few parts, retested it, and it took a fair amount more effort

and a couple million dollars more than we had expected to get it into a state where everybody, 

including the reliability folks and independent observers, felt like we were in as reasonable a 

posture as possible, but we did do that.

There weren’t any abnormal hiccups, I’ll say, in that development. There’s always a few 

issues, like I think we had a few problems with one of the boards looking a little funny, and we 

had to decide that it was okay that it looked a little funny. We went through a little extra test 

program on it, and everything ended up fine in the end. But I think from a spacecraftdevelopment standpoint, that probably was the area that had the biggest concern.

As I mentioned before, we had a lot of concerns about converting from the older RAD 

6000-based architecture for the avionics to the more modern RAD750 architecture and the

software changes that went with that. That actually went remarkably smoothly. There weren’t 

really any issues at all related to that. There weren’t any issues. The software conversion went 

per the plan. We did have a problem with our aeroshell, in that when they were applying the 
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ablative material, they didn’t follow right process, and so we ended up with some issues with 

there being some bubbles potentially in the material, so we had a big effort to go through to do a 

little bit of rework but also to go through a pretty extensive verification program to make sure 

that we weren’t going to essentially have one of these bubbles end up getting burned through by 

the heat during the landing process.

That was probably the only area where Lockheed Martin kind of had a screw-up, but 

other than that, they did a great job developing the whole vehicle, rebuilding the vehicle. Quite 

honestly, I think they would have been under their total contract cost probably by at least 5 

million, I think, if we had launched on schedule in 2016, because they had really done a very 

efficient job in terms of the whole effort there. I mean, they did a great job. During the course of 

trying to get to the 2016 launch, they replanned the ATLO program, I think probably at least five 

times, in a hugely significant fashion, and probably a couple of dozen more times with minor 

tweaks. And they had developed a way for us to essentially almost—if we had delivered the 

SEIS like two months before launch date, they had kind of figured out, “I think we can get 

through all the testing that we need to get done, even at Vandenberg, and be able to launch

successfully.” But, of course, the SEIS never ended up making it there.

But spacecraft-wise, we really did not have much of any issues. It was probably one of 

the smoother developments that I’ve been involved in.

Q: So you got to spend your time instead worrying about the instruments.

Hoffman: Yes, yes. Like you had asked me initially, initially I was very concerned about the 

spacecraft for a lot of different reasons. That kind of relatively quickly transitioned into a couple 
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of specific things, like the radar was a specific thing early on that we were concerned about 

making sure we could requalify that. And then probably around 2013, so that was maybe a year 

in, they started getting a little inkling that maybe things weren’t quite as smooth for the 

development especially of the SEIS as we had expected.

And then 2014, I think about May of 2014, I was getting very concerned with the SEIS, 

and I started to have regular calls with the project manager from CNES about maybe we should 

send Ken Hurst specifically, but maybe we should send some folks to Paris area and kind of 

embed them with Sodern and IPGP. Sodern was the company developing the SEIS as the 

industry partner, and then IPGP was the university that was essentially running the contract.

And there was a lot of pushback initially. “You shouldn’t be sending people there.” Part 

of it was because the CNES people didn’t have anybody there and they didn’t want JPL people

running around talking to those folks without CNES being present, which is not unreasonable. 

And then there was a certain amount of pride, which is a good thing to have, but there was a 

certain amount of pride that it was their job, not our job, to get it delivered. So I was pushing on 

that for a couple of months without much success.

But then in July of 2014, when Sodern was supposed to be delivering a whole bunch of 

flight VBBs to Sodern for, like, the final testing, they essentially all did not work in pretty much 

the same way, and that was the contamination issue I think you’ve already heard about. But after 

that, we were actually able to start getting a stronger presence and were able to demonstrate we 

actually would be able to help them, not just hinder them, in terms of the recovery effort, and it 

really changed the nature of our relationship for the better, I’ll say.

But one of the things I found out around that timeframe which was really bothersome was 

that because of the nature of the way that CNES and ESA and most of the European space 
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agencies do their contracts, and their history of almost never making a launch on schedule

because everything’s pretty much a fixed-price contract that they do with the people delivering 

stuff, almost everything always slips. Once we got close to the timeframe of things are not 

looking good for making the deliveries, there was some aspect of surprise, almost, from 

contractors like Sodern that we were actually serious about trying to make a 2016 launch. It was 

like, “Well, we didn’t think you were actually going to make it, so we didn’t really put in the 

kind of effort that we would need to to make it, because we figured everything slips, and we 

figured you were just going to slip,” which really annoyed me, and I read them the riot act 

endlessly about the fact that that’s not the case. But certainly that contributed to us probably

losing around six months in the beginning portion of the project, which I never fully appreciated 

until those six months were already gone, because people just weren’t working as hard as they 

could have or should have to make a 2016 launch. But that’s one of the geopolitical, kind of 

cultural things, I definitely did not appreciate at all heading into the InSight mission, but now I 

understand lots of things about the culture and how those projects in ESA and CNES are run.

I ended up finding out that Wednesdays in France, kids under the age—I think under 

third grade, they don’t go to elementary school, so the moms have to stay—it’s always the mom, 

or almost always the mom has to stay home and watch the kids, and so if you have women that 

have younger children, they almost never work on Wednesdays, and it’s just a known thing, so 

there’s a kind of built-in inefficiency there.

I also found out that it’s a requirement to take two weeks in a row off in the summer, and 

if you don’t take two weeks off in a row in the summer, the company actually gets fined by the 

government. So I had to go through a process of—I actually talked to the education minister 

about can we get exemptions for people during the timeframe that we needed to have work done 
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in the summer so that Sodern didn’t get fined. It was crazy. It was, like, these things that you 

never actually think about that are very important within one culture that definitely affect your 

ability to get planetary missions launched.

Q: That’s interesting. Yeah, it’s very much not JPL culture, anyway—

Hoffman: No.

Q: —where missing a launch is a crisis.

Hoffman: Not to say it’s wrong. Yeah, it may be much more—the work-life balance is definitely 

in full force in France, in fact, most of Europe. The Germans, which you always look at as, you 

know, perfectly efficient workers, they kind of have the same rules, they’re just quieter about it, 

and somehow they manage to somehow get all their time off and still get their work done, but 

they have kind of the same rules, as it turns out.

Q: Yeah, there’s much more—I don’t know. There’s more integration in corporate and union 

management in Germany than we have ever been used to, and we don’t, of course, have unions, 

but the rules for us are set very differently because of that, I think.

Hoffman: Yeah, like in Toulouse they actually require that people only have to really badge in to 

get into the facility, but they’re supposed to badge in and badge out of the cafeteria because they 

want to be—from a rules standpoint, you have to give your workers at least an hour for lunch. 
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You can take an hour for lunch, and if you end up not going to the cafeteria, then there’s 

something else. I don’t know exactly what you have to do, but you have to basically attest to the 

fact that you didn’t just work through your lunch.

I mean, there’s lots of things like that that I never had any appreciation for and then I 

became kind of an expert at. Like the school year, there’s like three different times during the 

year that you can pretty much be guaranteed that most families are going to be out of work, not 

at work, so you can’t really guarantee to get anything done.

Early on in the project, I always noted that there was, like, these issues getting meetings 

established at certain timeframes, like right after the Christmas break. Like, you think, okay, 

well, the first week back, you could do a meeting. Well, it turns out that first week back for most 

people in the U.S., there’s still another week off for people that have kids in school, and 

daycare’s not established, generally, in France, at least, and so the parents usually take that extra 

week off. And then there’s a week in the spring that pretty much everybody takes off, and then 

there’s a week in the fall that pretty much everybody takes off.

And it wasn’t until probably a few years into it where I got to know enough of the 

managers well enough that they kind of let me know exactly what was going on, but I found out, 

oh, yeah, you can’t really expect any work to be done in those three weeks of the year, because

half the team is going to be gone. And that’s just the way it is. They’re going to be gone, whether

they want to be gone or not, almost. So it was just fascinating, fascinating culturally. [laughs]

Irritating as a project manager for a planetary mission, but it was very interesting.

Then I don’t know if Ken told you, but, like, at Sodern, they would do barbecues on 

Wednesdays, and they would have, like, some beer in the afternoon, and so basically every 

Wednesday in the summer, at least, you wouldn’t get any work done after, like, 10:00 o’clock.
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Q: Yeah, because your whole afternoon is at the barbecue, yeah. [laughs]

Hoffman: Because they go to the barbecue and then they have some beer, then you don’t want 

them around flight hardware at that point.

Q: Right. [laughs] So it’s good for morale and not good for getting work done.

Hoffman: No, no. [laughs] Yes, those people, they were all very happy. [laughs] But they 

weren’t overly productive in the sense of how we measure productivity, certainly within the U.S. 

or especially at JPL.

Q: Fascinating.

Hoffman: It is. I learned many, many things from InSight, and only some of them were related to 

engineering and project management. [laughter]

Q: Well, knowing your partners’ schedules would certainly fit into the project management

bucket, anyway.

Hoffman: Yeah, and understanding the cultural aspects of people is also extremely important in 

terms of both expectations of what productivity can be, as well as motivation, because one of the 

bigger challenges we have, and certainly I had, is on these missions where you’re partnering 
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mostly internationally, but when you have a partner who is making a contribution, meaning 

you’re not paying them to do something, they’re doing something with their own money and 

giving it to you for free, essentially, you don’t have any direct ability to tell them what to do, 

because it’s the gold rule, right? They who has the gold sets the rules. If you’re not giving them 

any money, you can’t exactly tell them what to do. You can make suggestions, you can do 

whatever you need to do.

But if you understand the culture, then I think you have a better shot at figuring out how 

to motivate without a contract or without money. So certainly with both the French and the 

Germans, they have a lot of pride, and that was one of the things that you can appeal to in terms 

of motivation and trying to get them to do what we consider the right thing, whether it be 

additional testing or coming through on their commitments for delivery on a certain date of a 

certain element or whatever it is. So once I kind of figured that out, it made the discussions of 

trying to get them to do the right thing, by our definition, a little bit easier. There’s still a lot of 

discussion, a lot of just constant talking to get things done, but at least I came at it from the 

standpoint of having some knowledge of what that discussion should be around. So I don’t know 

if that made sense or not, but—

Q: Yeah, I think that does make sense. Knowing how to influence people that you can’t 

command is a leadership quality, right?

Hoffman: Right, and you need to understand what the motivation is, and some of it is a cultural 

thing, so, yeah, that’s exactly it. It’s like how do you motivate people that you have no direct 

control over. And a lot of it comes down to personal relationships and appealing to them, their 
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sense of pride as an engineer or manager or scientist, making them feel like they’re part of the 

team, which they are, and then letting them know how their contributions as a valued team 

member is going to make a difference in terms of the overall success of the project, and how the 

overall success of the project is going to reflect positively on them, and that’s important, and 

positively on their team and positively on their agency or their company, and then ultimately on 

their country. It actually ended up it is a big deal for France to have had the seismometer, 

actually I think one of their most expensive instruments they ever developed.

Q: And ultimately very successful.

So one of my questions I’ve got down here was precisely about how JPL went about 

supporting the SEIS development. You’re saying we sent Ken Hurst over and ultimately a 

number of other people. How was that organized and paid for at JPL, given that initially you 

started out with those instruments supposedly being free?

Hoffman: Yeah. So we had a few different types of people that we sent out there, because

initially our problem was contamination, so we sent Ned Ferraro, one of the best contamination 

people on the planet, out there to help them out, and we thought it was going to be initially just 

like a review. It ended up that Ned and another contamination guy spent a huge amount of time 

out there, first figuring out what the problem was, figuring out how to fix the problem, and then 

installing processes, procedures, and facilities that would not allow that problem to continue, and 

that took several months of Ned’s time and other folks’.

Also at that same timeframe, we brought out—we actually had two different guys that 

were there from the QA [quality assurance] standpoint almost continuously, Vazarik 
21

Gharakanian and Greg de los Santos. But they were there almost the entire time through 

ultimately delivery in 2017, so they spent like five years almost constantly in the Paris area, 

sometimes going to Madrid or Berlin for the other stuff. So there’s those two aspects.

Then we had the engineering support where Ken was the main person as the SEIS

instrument systems engineer. Our mission assurance manager went out several times, Linda 

Facto. Our overall payload system engineer, Jason Feldman, was out a lot. And then Jason 

Willis, our PSE, was out there a lot. Then I went out a fair amount as well. Our payload manager, 

Ed Miller, went out there a fair amount to sort of provide the management for us. So I guess we 

had maybe four different aspects. We had the engineering arm, which was a variety of different 

people, but Ken by far the most, the contamination control aspect with Ned, and then the overall

mission assurance, quality-assurance leg, and then the management leg. So it took kind of all of 

those efforts pushing at different parts of the sponge to eventually get stuff delivered.

We had planned some of that effort, a little bit of time from Ken, certainly the payload 

manager initially, but the rest of the effort, which ended up being about—I calculated at the end 

it ended up being about maybe $20 million—that was all paid for out of my reserves.

Q: So those supplemental—it was entirely in your previously-planned reserves.

Hoffman: Yes, and then when we missed our launch in 2016 and had to try for 2018 launch

opportunity, the plan that I put together included a significant amount of effort for supporting 

folks in France and in Germany, but we also took on some additional scope. We took it from 

Sodern, which was specifically for building the whole sphere, what we called the evacuated 

chamber. Building that whole effort, building that whole thing, including the connectors, was 
22

done at JPL, so that was another—I think we spent, in the end, around 13 million, roughly, for 

that, to get that delivered to Sodern and help with the integration of that activity and everything 

to get qualified, and that effort was led by Jeff Umland, so that’s why he might be a good person 

to talk to at some point.

Q: Okay.

Hoffman: So probably our total effort to get the SEIS delivered maybe ended up being between 

30 and 40 million dollars over the course of the project that was unplanned for, and then I know 

that CNES—I don’t think they have an official record, but they spent well over $100M of their 

own money getting SEIS delivered.

Q: Good heavens.

Hoffman: So it was not a cheap instrument.

Q: Nope. It wasn’t a cheap free instrument. [laughter]

Hoffman: No, not for anybody.

Q: No. Amazing. And also a little troubling, too, because there have been dreams of sending 

multiple seismometers to Mars, and those dreams sound even more like fantasy now because of 

what you’re saying, just in cost.
23

Hoffman: If they wanted to reuse those, they probably could get them built a lot cheaper. In fact, 

they are flying the spares that we built, and they’re using them on the Moon, some of the same 

people.

Q: Right. I remembered that they were also part of an upcoming Moon mission.

Hoffman: Yeah. Pretty much all the same people. Pretty interesting. [unclear].

Q: But makes sense. [laughs] Yeah, it should be a great seismometer for the Moon, right?

Hoffman: Yeah, yeah.

Q: So let’s see. How were the project’s challenges with instruments, delays in spacecraft, etc., 

communicated to JPL management and to Headquarters?

Hoffman: So that’s one area that I think we did a really good job on, frankly. As soon as we 

started having problems that were noticeable, like in May of 2014, I started communicating with 

my director, who at the time was Firouz Naderi, and his deputy, who was Keyur Patel. I had a 

couple of different ones that went through at different points. But I started communicating with 

them pretty clearly right away and let them know what my plan was in terms of trying to get 

people sent there, and letting them know, “Look, I’m having difficulty with CNES allowing us to 
24

go there,” and I think they were good about communicating that up to Charles Elachi, who was 

the JPL director at the time.

When we had the problem when we didn’t get stuff delivered in July, I doubled down on 

the reporting and the concerns and everything. I can’t quite remember exactly when it was, but I 

think it was probably sometime maybe in early 2015, I think, is when Charles started helping by 

having a monthly phone call with his counterpart at CNES, Marc Pircher—who Charles knew 

from all the different activities that they had done in the past, and basically it was just mostly a 

management call to let their management know that JPL management was concerned, and having 

them step in and provide some additional support and assistance to the CNES team, because they 

were a little bit chronically understaffed initially, and so getting that extra support, I think, was 

helpful to them.

At first, they were reluctant to get it, but then after a little bit, they realized, “Oh, we 

should be able to use this to our advantage,” which they did. The got some additional staff. They 

put a resident person at Sodern and IPGP. Took them a long time to find the right person, and we 

already had somebody there, but it ended up working out pretty well from that standpoint.

I wasn’t shy about communicating the issues forward to my program executive, who 

communicated that with SMD, and I think there was certainly a lot of reporting, even in 2014, 

but by 2015, when we were getting to the point where we really had to get stuff delivered in 

order to make the launch, I was having, I think, at least weekly reports up to Grunsfeld, who was 

the SMD director at the time, probably starting about mid-2015. So he was getting every week a 

report from me on what the progress was, what our setbacks were, what our plans forward were.

As we were going through 2015, we had a few victories. Late 2014, we solved the 

contamination problem. Early 2015, we started having some other noise problems. We 
25

essentially got through all of the VBB-related problems by the summer of 2015. The team did a 

great job in solving that set of problems, so that we had good VBBs, we were getting them 

manufactured at a reasonable rate. We didn’t have a lot of them. We only really had three that 

were good, but we had enough VBBs because we only needed three.

Then we started in on, like, the overall qualification program of the package, and that’s 

where we ended up with the sphere collapse, which delayed the qualification of the overall 

sphere, which then delayed us finding out about the fact that they had procured the wrong type of 

connector. They didn’t procure connectors that were actually going to ever work at our 

temperature or vacuum considerations. By that point, that was about, I think, August of 2015 that 

we had the notification that basically they had failed their final environmental test at CNES in 

Toulouse when we were going out to get ready for a pre-ship review. That was the worse preship review of all time, in my opinion. It set us back. But we had spent so much time trying to 

solve the VBB problem, and then we had the sphere collapse, it never allowed us to qualify the 

overall evacuated container portion of the system.

Then we—I’m sure you heard about it from Ken—we launched a huge effort to try to 

figure out how to basically put a Band-aid on it through a variety of different methods, and we 

spent a couple of months on that. We failed again in October, early October. I remember that 

specifically—it was the 8th of October—because there was a science team meeting in Zurich. I 

was supposed to be getting on a nice boat to do a tour of Lake Zurich with the rest of the science

team. I showed up a little bit late. They were nice enough to hold the boat. I get on the boat. 

Literally as I step onto the boat, I get a call from Jason Feldman saying, “We’ve failed the test,” 

which was not a terrible surprise, but it was still hugely unfortunate, because we thought this was 

our last best chance to fix the problem.
26

Bruce was on the boat with me, Philippe [Lognonne] who was the SEIS PI was on the 

boat. Ken was not there, he was also at the test. So we spent the entire boat ride, which I 

understand was a beautiful boat ride, talking with Jason Feldman about what to do next. 

Basically, when we finished the conversation, we had redocked. [laughs] So I never actually

looked out. It was, like, a sunset cruise. I never actually got a chance to look out and enjoy the 

view. But that was kind of par for the course, because I never had a science team meeting until 

the very last one after we launched, that something bad didn’t happen that required that I stop 

attending the science team meeting for pretty much either a portion of a day or the rest of the 

science team meeting. So, entertaining.

Q: Entertaining, but you don’t make it sound very fun. [laughter]

Hoffman: No, no, it was not overly fun. Actually, I thought I was going to have fun on the 

science team meeting in—I think it was 2016. No, I’m sorry. It was 2017. It was early, it was, 

like, springtime. We were going to Oxford for the science team meeting, and as soon as I landed 

in London and started on my way to go to Oxford, where I was presenting on the first day, I 

started to get word that things were, from a schedule standpoint, not so much technically, but 

things were not going well at Sodern. There was some consternation we were going to lose like a 

couple of weeks, or we’d already lost a couple of weeks; it wasn’t exactly clear.

So I gave my presentation on Monday. I think I landed on a Saturday. I spent Sunday in 

London, and that’s where I heard about this potential issue. On Monday, I gave my presentation, 

and then I took the train over to Paris at the last minute with the guy who was running the SEIS
27

delivery at the time, Brian Bone, and just so I could have a conversation with them about 

needing to make sure that they didn’t miss their delivery, which was in, like, two months.

So by the time I got there, actually, the fact that I was coming, the problem got solved, 

but, nonetheless, I never attended the science team meeting, other than my presentation. Science 

team meetings never were very good for me on InSight. Almost every time, there was some kind 

of issue.

Q: We’re about to run out of time, so we’ll probably have to come back to this, but I wanted to 

ask you to tell me your story of the day you decide you have to delay the launch.

Hoffman: Yeah. So kind of continuing with the previous discussion, I had been communicating

pretty clearly with my management, with Charles. Along the way, I was sending out the weekly 

reports for months, leading up to the problem that we had in August, the problem that we had in 

October of 2015, how we’re going to try to make ATLO still work and not be too risky. We had 

had lots and lots of those discussions.

After the October incident, we kind of knew we had one more chance, and this was really 

going to be our last chance, and we knew it was not likely to work. I let people know, “Look, 

we’re going to try one more time to seal the sphere. We think we have a solution that might 

work, but it’s not really high probability.”

So I got notified on December 22nd, 2015, that the last chance really to have a shot at it 

had failed, and, of course, the team, to their credit, had figured out another way. “If we just do 

this other thing, maybe we’ll make it.”

And I’m like, “No, we’ve tried hard enough. We’ve done enough.”
28

So I was actually sitting at my cabin up in Mammoth, because I was going to try to have 

a decent break, but I was still working, of course. So I’m sitting up there. I think it was actually a 

holiday day for JPL. I call up Firouz, I call up Charles, I kind of let them know. I said, “I think I 

need to let Grunsfeld know.” And I said, “Do you guys want to call him? You want me to call 

him?”

They said, “No, you go ahead and call him. If he has questions, you can address them.” 

Because I think at that point they had enough confidence in my messaging that they didn’t feel 

like they needed to be on the call.

So I called up Grunsfeld on his cell phone and let him know we had tried, what we had 

tried, to let him know, “I told you it probably wasn’t going to make it. It’s not going to make it. I 

think really the right thing to do is to pull the plug.” I said, “I’d like you to give me a chance to 

come back to you and tell you in March what we need to do to make a 2018 launch, because I 

think I can get to a plan by then.”

So he agreed, “Okay, let’s do that.”

Then I sent a note off to the team and let the team know, “Look, we’re going to stand 

down. We’re going to scrub for the 2016, but we’re going to pull together and figure out a plan 

for a 2018 launch.” But I told everybody, “Just don’t do anything until we come back on the 4th,” 

or whatever the day was, the next Monday after New Year’s. “Take the next week and a half,” or 

whatever it is, “off. Don’t think about InSight. Let’s come back batteries partially recharged and 

let’s figure out what we need to do to go forward.”

So I started traveling that first week and helped everybody come up with a plan that 

ultimately got us to 2018. But, yeah, that was tough. It was not a fun call to make, but it was the 

right decision.
29

Q: Yeah, and I’m sure it caused a lot of angst for people who’d worked very hard to get to that 

point and just couldn’t make it.

Hoffman: Yeah, and they kept wanting to try and try and try, but ultimately you have to say 

when enough is enough, and that was that point for us.

Q: Yeah. Okay. Well, thanks for your time. We’re out of time, so we’ll probably have to come 

back to finish up. They’re great stories, though. So thank you, and we’ll talk again. I owe you 

still your corrections from the last transcript, and, of course, you’ll get this one again in a couple 

of weeks.

Hoffman: Okay. No worries.

Q: Thank you.

[End of interview]