In a new series, the editors of NASA Tech Briefs magazine catch up with everyday engineers about their unique responsibilities and challenges. This week, we highlight fellow reader and aircraft navigation system professional, Sid Wood.
Sid Wood, Senior Scientist Engineer
Field/Expertise: Navy aircraft navigation systems.
What are your day-to-day responsibilities?
Sid Wood: I worked for the Navy as a civil service engineer for a number of years. I’ve since retired from civil service and now I’m working for a private company. I work out of the Patuxent River Naval Air Station. Specifically the Naval Air Systems Command (NAVAIR) organization is headquartered there. I support one of the departments. Their expertise is with navigation systems. We develop the navigation equipment of various Navy, Coast Guard, and Air Force airplanes and aircraft.
I have some background in their operations, so that was a natural fit for me. What we have done in recent years is to develop a series of rate gyros that can be used on lots of different platforms: fixed-wing, jet aircraft, various turbine-powered airplane, propeller-driven airplanes, as well as helicopters. Each one has a peculiar environment, either from an operations viewpoint or from a vibration or pressurization viewpoint.
What’s the biggest engineering challenge that you face?
Wood: Those varying requirements get to be stumbling blocks for the vendors that make the product. It’s all commercial industry that produces it, but they have to do it to the government’s specifications. And that’s where the problem comes in: What is that specification? Does that reflect something that the industry can do? Does technology exist for that?
Developing the new technology gets to be a pricy proposition. If you can apply existing technology to that particular task, then you’re way ahead of the game, both in time and dollars spent.
When I write a specification, I try to get what the cutting-edge requirements would be and then make those with existing technology. Sometimes the vendor, who would potentially use this, doesn’t even know that that technology even exists. Pulling those things together is an art form in a way. They don’t teach you that in engineering college.
What’s the next part of your process after settling on the requirements?
Wood: The vendor is selected, and they proceed to come up with a “first-article” type of equipment. You always produce 5-6, 15-200, or however many I/Os make sense, for testing. Invariably there are problems, depending on the expertise that the company puts on it, their understanding of the specification, their background in producing similar equipment, and, of course, how well guys like myself have put together a specification. Did we say it right? Did they understand what was written? We get into a big semantics battle sometimes.
Once they produce these, we have to perform test & evaluation (T&E) activities. You make sure that you referee the [product] for the vendor. They know their job, but are they testing it in the manner that you thought it was supposed to be used? Even though they are hardcore test and evaluation engineers, they don’t necessarily have the insight that the program management does, as far as what the fleet needs and what’s practical. That’s where we get to adjudicate that type of situation. There’s a lot of subjective judgment. Every aircraft design that ever existed is a compromise of different requirements. It has to be faster, it has to be stronger, it has to lift more, but there are tradeoffs. If you go fast, that means you’re burning a lot of fuel.
What’s next after the testing process?
Wood: We finally get it to the point where this is a product, and we can get it out and into the fleet. Once the company goes forward with full-rate production, then we try to get it deployed. There are all sorts of ways to go about getting it out there. You can just put it on the shelf; when the old one breaks, they get the new product. Or you can do a forced retrofit: You set up these kits, you drop ship into the squadrons, and say “Here are the instructions on how to install the thing. Make it happen.” Sometimes there are problems with that because the people who write the instructions don’t necessarily write them so that you get the product that you expect. Then I get called in again: “Well, wait a minute. We didn’t quite do that right, or you should have set it this way, or that wire goes over here and not there.”
Out of all those phases, which one, do you think, is the most challenging?
Wood: The most challenging part is getting the commercial vendors to understand what’s needed: What does the end-product need to do? There’s some hand-holding that goes on there.
Of course, as a consultant, that comes to me again, to try to work with the company engineers to teach them as they go along. And, of course, people have a lot of ownership [issues]. They don’t like to give up on that. You’ve got to put a little diplomacy in there sometimes. Sometimes company management gets into it because they see the bottom-dollar figures are changing, or they dig in their heels and say “You’re getting requirements creep in here.” You’re refereeing between the customer, that is, the Navy and Marine Corps or the military, and the vendor, who’s trying to produce a product and make the best they can out of it. Of course, they have to earn a profit too. I come across lots of government administrators who don’t understand that principle, that the vendor needs to make a profit if they expect to stay in business.
From an engineering perspective, as you’re putting together specifications, what specific tool do you think helps you the most? What do you think is on the cutting edge?
Wood: I need to keep up with the cutting edge on technologies. The Tech Briefs provide those sound bytes to let me know, without requiring excess time to get it. I read a lot of publications, all kinds of pieces and bits. We have to budget time, so I can’t go into depth on every one of those things. I’m always looking for that new development. With the Tech Briefs, yes, a lot in there is out of scope and out of field for me. What I’m looking for is those applications in my field, in navigation. It gives me a quick synopsis. There are always references of who wrote it and where are they coming from. If I want to get more in depth, I can pursue that.