The Lockheed Martin F-16 Fighting Falcon and Boeing’s F/A-18 Hornet both emerged in the late 1970s as lower-cost supplements to the U.S. Air Force’s F-15 Eagle and the Navy’s F-14 Tomcat.

Over the years, both aircraft have evolved. Boeing’s (then McDonnell Douglas) classic F/A-18A Hornet has been transformed into the larger, more capable F/A-18E/F Super Hornet--which is effectively a completely new airframe. The F-16, meanwhile, has evolved from a lightweight dogfighter into an extremely capable multirole strike fighter. However, both designs are nearing the end of their lives as the new Lockheed Martin F-35 Joint Strike Fighter begins to supplant both types on the international fighter market.

The U.S. Navy is buying some number of additional Super Hornets--a total of 16 spread over the fiscal year 17 and 18 budgets. But exactly how many additional new F/A-18’s it will ultimately buy remains unclear--but eventually the service will only buy new F-35Cs. The U.S. Air Force stopped buying new F-16s years ago in favor of the F-35. That means that both aircraft will have to fight for buyers on the international fighter market to keep their production lines open.

However, there are few immediate sales prospects--mostly to U.S. allies that Washington won’t sell the F-35 to for the time being. Those nations are mostly in the Middle East or are nations that probably can’t afford the F-35. Kuwait and the United Arab Emirates could be potential prospects. But a Boeing effort to sell new Super Hornets to Kuwait has stalled.

Lockheed has some recent success with the U.S. government agreeing to sell Pakistan eight more F-16s. The company also hopes to sell the jet to Colombia, Bahrain and Indonesia--but Jakarta seems to have picked the Russian Su-35 over the U.S.-made plane. Meanwhile, a potential deal for thirty additional F-16E/F Block 61 fighters to the UAE is still pending. Until more sales materialize, the company is funding some of its suppliers to keep its subcontractors going.

However, while small batch orders might keep the production lines open for a few years, longer term survival depends on finding a large buyer. Both Boeing and Lockheed seem to have their eyes set on India. The South Asian giant has an urgent requirement to replace its ageing MiG-21s and other older Soviet-built hardware. There could be a potential to sell more than 126 aircraft to New Delhi.

India, however, is not content with importing jets--it wants to build the jets domestically. Boeing and Lockheed have indicated a willingness to build the jets in India, but it remains to be seen if New Delhi and the Washington can come to an arrangement.

Dave Majumdar is the defense editor for The National Interest. You can follow him on Twitter: @davemajumdar.