Q&A with Air Force Chief of Staff Gen. David Goldfein.

* Gen. David Goldfein is the 21st Air Force Chief of Staff. On July 31, he spoke with National Defense staff writer Connie Lee to discuss a wide range of issues facing the service. The following Q&A has been lightly edited for length and clarity.

Q: When do you anticipate the Air Force fielding an operational hypersonic weapon [the Pentagon's top R&D priority]?

A: Right now we're on track to reach... early initial operating capability in FY '22. So we're doing this under the new authorities granted to us by Congress. The 804 authorities allow us to prototype and experiment. So we're moving pretty quickly. One of the things that's ... an important part of our story, of course, is how closely we're aligned with the other services. ...We're taking the best of breed from each service. And quite frankly, we don't care which service it comes from. If it works well, we incorporate it quickly.

Q: What is the timeline for the hypersonic conventional strike weapon program?

A: It's going to go through design reviews in '20, testing in '21 and we're supposed to reach IOC in '22.

Q: Several European countries have unveiled plans to build sixth-generation fighters. How far along is the Air Force in thinking about a sixth-gen fighter? What kind of capabilities might it have, and how would it be better or different than fifth-generation aircraft? When is the Air Force hoping to start developing and fielding a sixth-gen fighter?

A: Anytime we have competitors who are in the ring, the service benefits and the nation benefits because it drives innovation and drives costs down and we get a better product. So I'm actually pretty excited about it. I just tell you that I'm not locked into sixth-generation as being a single platform. I think it actually limits our thinking if we go down that path. I don't know right now whether it's a platform, it's a number of platforms, it's a family of systems, it's a whole domain. I want to keep that wide open so we can really drive towards game-changing technology as we go forward.

It has to be able to penetrate. It has to be able to persist. It has to to be able to protect. It has to be able to proliferate. And it has to be able to punish. And so this ... family of systems, in my mind, is designed to go do all of those things. It has to be able to penetrate the worst potential defenses we could be up against. It has to be able to have the legs to persist in that environment for as long as we need it to persist. ... I'm not...