Payload fairing

A payload fairing is a nose cone used to protect a spacecraft payload against the impact of dynamic pressure and aerodynamic heating during launch through an atmosphere. An additional function on some flights is to maintain the cleanroom environment for precision instruments. Once outside the atmosphere the fairing is jettisoned, exposing the payload to outer space. The standard payload fairing is typically a cone-cylinder combination, due to aerodynamic considerations, although other specialized fairings are in use. The type of fairing which separates into two halves upon jettisoning is called a clamshell fairing by way of analogy to the bifurcating shell of a clam. In some cases the fairing may enclose both the payload and the upper stage of the rocket, such as on Atlas V and Proton M. If the payload is attached both to the booster's core structures and to the fairing, the payload may still be affected by the fairing's bending loads, as well as inertia loads due to vibrations caused by gusts and buffeting. Payload fairings have usually been either burned up in the atmosphere or destroyed upon impacting the ocean, but SpaceX began to retrieve them in the 2010s with a fairing recovery program. On March 30, 2017, SpaceX successfully retrieved a fairing intact for the first time in history. For a second time on June 25, 2019, SpaceX was able to catch a fairing from the Falcon Heavy STP-2 launch. After this, SpaceX began reusing its fairings, which are manufactured at a cost of per orbital launch; its CEO, Elon Musk, stated that retrieving the fairings before they touch sea water "makes refurbishment easier". While a conventional payload fairing is typically jettisoned from the launch vehicle and recovered at sea, Rocket Lab's Neutron Rocket proposes to use a fairing that is integrated into the vehicle. This attached fairing would open during stage separation to release the second stage and payload and close again after stage separation, then return with the first stage when it lands back on Earth.