The U.S. Air Force’s quick-reaction program to provide connectivity between the premier F-22 fighter and legacy, fourth-generation F-15 appears to be slipping behind schedule.

The Boeing Talon Hate pod, which is designed to provide that connectivity, was requested by Pacific Air Forces as a quick-reaction project needed to link the stealthy F-22 with legacy fighters.

Industry sources, however, suggest Talon Hate is being "rebaselined" — the Pentagon’s word for delayed — though it appears there is no significant snag.

The Air Force says deliveries will be later this year. "As with all acquisition efforts on the leading edge of technology, cost and schedule must be balanced in the best interest of the government," Air Force spokeswoman Ann Stefanek said. "Currently, we are planning for deliveries starting in fall 2015." She declined to say whether the program’s cost has increased, but noted that "no estimate-at-completion decisions have been made to date."

Typically, the service has a basic estimate on projects prior to starting them, even for cost-plus projects such as Talon Hate. The original cost of Boeing’s contract was $134.6 million, Stefanek says. "Decisions will be forthcoming" on the final cost and schedule, she adds. Boeing is required to build and deliver the pods; the Air Force is expected to integrate them onto the F-15C, which requires some modification to allow for proper antennas for items such as the satellite communications capability.

Though a small project – only four pods are slated for fielding – Talon Hate is important to watch. It is a bellwether for projects to come that are designed to provide connectivity among a shrinking fleet of Air Force fighters. With the stealthy F-22 buy truncated at 183 aircraft and F-35s being introduced into service far more slowly than planned, the Air Force is being forced to devise a connectivity regimen among these platforms to maximize their capabilities in battle.

Both Air Force Chief of Staff Gen. Mark Welsh and Air Combat Command chief Gen. Herbert "Hawk" Carlisle have highlighted the need for a "5th to 4th" communications capability, though the Air Force’s programmatic plan to field it has not yet gained steam.

Talon Hate is being managed by the Air Force Tactical Exploitation of National Capabilities (Tencap) office; a congressionally mandated office designed to enhance interoperability among Air Force systems. The Talon Hate pod, to be carried on the F-15C, will include an infrared search and track sensor (missing on the F-22), a Multifunctional Information Distribution System link (similar to the ubiquitous Link 16), satellite communications link and an air-to-ground link. At issue is providing connectivity to the F-22, which could be operating with stealth tactics behind enemy lines. Use of Link 16 would reveal the F-22’s location. Talon Hate will undergo a utility evaluation once fielded and provide lessons for the Air Force as it embarks on its 5th-to-4th program of record, called the Multi-Domain Adaptable Processing System (MAPS). Carlisle, a self-described "believer" in pursuing a 5th to 4th program, says the service will "start increasing the volume of money for [MAPS] in ’17." He says work in the laboratories has "showed great promise," and "we’re not there yet but we are moving in the right direction. I’ve pushed it because it think it is incredibly important in the joint fight."

Though Boeing is working on Talon Hate, Lockheed Martin and Northrop Grumman are likely to compete for the follow-on MAPS. Lockheed officials have pushed the idea of pursuing a direct "5th to 5th" capability that would link the F-22, which uses its low-probability of detection/low probability of intercept (LPI/LPD) inflight data link (IFDL) – designed only for use with other F-22s – with the F-35, which uses the Multi-function Advanced Data Link (MADL). IFDL and MADL use different waveforms, preventing direct data exchange.

Through a series of demonstrations called Project Missouri, Lockheed is working on integration of the L-3 Communications Chameleon waveform for use on antennas operating in the L-band. Data transmitted via the waveform would be "spread" below the noise; only the proper receiver could "pull the data out" of that noise. The benefit to this approach, they say, is that they can make use of L-band antennas already on the fighters, eliminating the need for costly modifications.

Editor’s note: This story has been updated to correct how the Chameleon waveform operates.