If you look at El Paso International Airport on Google Maps, on the south side apron and across from a hangar that is labeled "Sierra West Airlines" (west of the NASA facilities) there is a small quad-jet plane:
The aircraft is about 20 m long and has a wing span of about 18 m:
The McDonnell 119/220 was an attempt at making a business jet by McDonnell Aircraft in the late-1950s. It had a configuration that was unique by bizjet standards, with four jet engines mounted in individual pods underneath a low wing; it could accommodate ten passengers in a luxury executive configuration but could carry as many as 26.
The McDonnell Corporation used the airplane as a VIP transport for a few years before donating it to the Flight Safety Foundation's research facility in Phoenix, Arizona. As of 2020 the single prototype is still extant, registered as N4AZ and stored at El Paso International Airport.
Only one such plane exists. Its first flight was in 1959.
This appears to be a McDonnell 119/220, a 1950s vintage business jet attempt (from before McDonnell merged with Douglas). The four engine layout with engines under the wings, coupled with the size, is very distinctive.
The one at El Paso is apparently a genuine rarity — there was only a single unit (the prototype) ever constructed.