The USAF just announced IOC (Initial Operational Capability) on their F-35A’s. While the USAF may be celebrating, many think there is a long road ahead for the Joint Strike Fighter.

60 F-35’s a year. That’s the number ACC General Hawk Carlisle wants to buy annually now that the F-35A has gone IOC. The Air Force announced, as expected on Tuesday, that the 34th Fighter Squadron from Hill Air Force Base had met the minimum requirements to be operationally capable. Now the concern is how many F-35’s can come off the production line–and how many Congress is willing to fund.

The USAF has requested to buy 43 for fiscal year 2017.

“My concern is buy rate,” the head of the Air Combat Command told reporters. “I need more faster, to replace aging aircraft, to get to a more economic order quantity.”

Way back before the numerous delays and problems began to mount for the JSF, the original plans for the F-35 called for much larger annual purchases. The Pentagon had to step back on its annual purchase commitment because the 5th Generation fighter was simply not making head way. Delays and cost overruns in the JSF program have also made the program a lighting rod for critics.

Detractors were still skeptical of the program, even in the wake of the 2 August IOC announcement.

Senate Armed Services Chairman John McCain (R-Ariz.), Senate Armed Services Chairman and no friend of the F-35, called the USAF’s IOC announcement “another important milestone in the Joint Strike Fighter program.”

But, he added: “The road ahead remains long.”

IOC is the minimum capability required to send the aircraft over to an operational war zone. With the F-35A now declared IOC, the USAF has 12 aircraft at the minimum level of combat capability. Additionally, only 77 F-35’s have been delivered to the USAF through the end of 4th quarter 2015. The full order calls for 1763 aircraft through the year 2037. IOC is a small but much needed start for the maligned program.