The U.S. Defense Security Cooperation agency, in its required notifications to Congress, said the sales would have a combined value of $307 million.
Switzerland is seeking participation in the F/A-18 Engine Component Improvement Program, spare and repair parts, system integration and testing, classified and unclassified publications and technical documentation, flight testing, support and test equipment, transportation, personnel training and training equipment for its F-18 fighters.
Included in the request is software development, U.S. government and contractor technical and logistics support services and other related elements of logistics support.
The estimated cost is $200 million.
"The proposed sale of this follow on support will allow the Swiss Air Force to extend the useful life of its F/A-18 fighter aircraft and enhance their survivability," the agency said. "The defense articles and services will be used to support the current Switzerland F/A-18 Hornet Upgrade 25 program and future upgrade programs.
"The Swiss Air Force needs this support to keep pace with technology advances in sensors, weaponry, and communications."
The principal contractors for the package, if approved, would be Excelis Inc.; Northrop Grumman Electronic System; Boeing; General Electric Aircraft Engines; General Dynamics Information Technology; Wyle Laboratories; MacKee Inc.; and Zenetex.
"The proposed sale will contribute to the foreign policy and national security of the United States by helping to improve the security of a friendly country which has been, and continues to be, an important force for political stability and economic progress in Europe," the agency said.
Switzerland operates 32 F-18 fighters.
Austria has asked the United States for three UH-80M Black Hawk helicopters, plus associated equipment, parts, training and logistical support.
The helicopters would be in standard configuration but with unique equipment for Austria, the agency said.
The country also seeks aviation survivability equipment; seven T700-GE-701D engines; three aviation mission planning systems; a transportable Black Hawk operations simulator; a number of AN/AVS-9 night vision goggles; and eight embedded global positioning systems with inertial navigation.
Communication security equipment, air worthiness support, facility construction, spare and repair parts and other equipment, tools and documentation would be part of the $137 million package, the Defense Security Cooperation Agency said.
The agency said the sales would improve Austria's capability for domestic search-and-rescue operations and border surveillance.
"The proposed sale will also contribute to the Austrian military's modernization goals while enhancing interoperability between Austria, the U.S., and other allies," it said.
Sikorsky Aircraft would be the principal contractor for the Austrian deal and the helicopter engines would be purchased from General Electric Aircraft Company.
If Congress approves the sale, nine U.S. government or contractor representatives would be required to travel to Austria for a period of up to five years for support.