\n<\/p>\n
As\u00a0NASA\u2019s\u00a0X-59 quiet supersonic research aircraft\u00a0continues a series of flight tests over the California high desert in 2026, its pilot will be flying with a buddy\u00a0closely looking\u00a0out for his safety.\u00a0<\/p>\n
That colleague will be another test pilot in a separate chase\u00a0aircraft. His job as chase pilot: keep a careful watch on things as he tracks the X-59 through the sky, providing an extra set of eyes to help ensure the flight tests are as safe as possible.\u00a0<\/p>\n
Having a\u00a0chase pilot\u00a0watch\u00a0to make sure operations are going smoothly\u00a0is\u00a0an essential task\u00a0when an experimental\u00a0aircraft\u00a0is\u00a0exercising its capabilities for the first time. The chase pilot also\u00a0takes on tasks like\u00a0monitoring\u00a0local weather and\u00a0supplementing communications between the X-59 and air traffic control.\u00a0<\/p>\n
\u201cAll this helps reduce the test pilot\u2019s workload so he can concentrate on the actual test mission,\u201d said\u00a0Jim \u201cClue\u201d Less,\u00a0a\u00a0NASA research pilot since 2010\u00a0and\u00a021-year veteran\u00a0U.S.\u00a0Air Force flyer.\u00a0<\/p>\n
Less served as chase pilot in a NASA F\/A-18 research jet when NASA test pilot\u00a0Nils Larson\u00a0made the X-59\u2019s\u00a0first flight on Oct. 28. Going forward, Less and Larson will take turns flying as X-59 test pilot or chase pilot.\u00a0<\/p>\n
So how close does a chase\u00a0aircraft\u00a0fly to the X-59?\u00a0<\/p>\n
\u201cWe fly as close as we need to,\u201d\u00a0Less\u00a0said.\u00a0\u201cBut\u00a0no closer than we need to.\u201d\u00a0<\/p>\n
The distance depends\u00a0on\u00a0where\u00a0the chase\u00a0aircraft\u00a0needs to\u00a0be\u00a0to best ensure the success of the test flight.\u00a0Chase pilots, however,\u00a0never\u00a0get\u00a0so close as to jeopardize safety.\u00a0<\/p>\n
Jim “clue” LESS<\/p>\n
NASA Test Pilot<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n
For example,\u00a0during the X-59\u2019s first flight the chase\u00a0aircraft\u00a0moved\u00a0to within a wingspan of the\u00a0experimental\u00a0aircraft.\u00a0At that proximity,\u00a0the\u00a0airspeed and altitude indicators inside both\u00a0aircraft\u00a0could\u00a0be compared, allowing the X-59\u00a0team\u00a0to\u00a0calibrate\u00a0their\u00a0instruments.\u00a0<\/p>\n
Generally, the\u00a0chase\u00a0aircraft\u00a0will remain\u00a0about\u00a0500 and 1,000 feet\u00a0away\u2014or about 5-10 times the length of the X-59 itself\u2014as the\u00a0two\u00a0aircraft\u00a0cruise together.\u00a0<\/p>\n
\u201cOf course,\u00a0the chase pilot\u00a0can move in closer if\u00a0I\u00a0need\u00a0to look over something on the aircraft,\u201d Less said.\u00a0\u201cWe would\u00a0come in as close as\u00a0needed, but for the most part\u00a0the goal is\u00a0to stay out of the way.\u201d\u00a0<\/p>\n
The up-close-and-personal vantage point of the chase\u00a0aircraft\u00a0also affords the opportunity to capture\u00a0photos and\u00a0video\u00a0of the test\u00a0aircraft.\u00a0\u00a0<\/p>\n
For the\u00a0initial\u00a0X-59 flight,\u00a0a NASA photographer\u2014fully trained and certified to fly in a high-performance jet\u2014sat in the\u00a0chase aircraft\u2019s rear\u00a0seat\u00a0to\u00a0record images\u00a0and\u00a0transmit\u00a0high-definition video down to the ground.\u00a0<\/p>\n
\u201cWe really have the best views,\u201d Less said.\u00a0\u201cThe top focus of the test team\u00a0always\u00a0is\u00a0a safe flight and landing.\u00a0But\u00a0if we get some great shots in the process,\u00a0it\u2019s\u00a0an added\u00a0bonus.\u201d\u00a0<\/p>\n
Chase\u00a0aircraft\u00a0can also\u00a0carry\u00a0sensors that gather data during the flight\u00a0that would be impossible to obtain from the ground.\u00a0In a future phase of X-59 flights, the chase\u00a0aircraft\u00a0will carry a\u00a0probe to measure the X-59\u2019s supersonic shock waves\u00a0and help\u00a0validate\u00a0that the airplane is producing a quieter sonic \u201cthump,\u201d rather than a loud sonic boom to people on the ground.\u00a0<\/p>\n
The instrumentation was\u00a0successfully tested\u00a0using a pair of NASA F-15 research jets earlier this year.\u00a0<\/p>\n
As part of\u00a0NASA\u2019s\u00a0Quesst\u00a0mission, the\u00a0data\u00a0could\u00a0help\u00a0open the\u00a0way for commercial faster-than-sound air travel over land.\u00a0<\/p>\n
Chase\u00a0aircraft\u00a0have served as\u00a0a\u00a0staple of\u00a0civilian and military\u00a0flight tests\u00a0for decades, with NASA and its predecessor\u2014the National Advisory Committee for Aeronautics\u2014employing\u00a0aircraft\u00a0of\u00a0all types for the job.\u00a0<\/p>\n
Today, at\u00a0NASA\u2019s\u00a0Armstrong Flight Research Center\u00a0in\u00a0Edwards,\u00a0California, two\u00a0different\u00a0types\u00a0of\u00a0research\u00a0aircraft\u00a0are available to serve as chase\u00a0for X-59 flights:\u00a0NASA-operated\u00a0F\/A-18 Hornets\u00a0and\u00a0F-15 Eagles.\u00a0<\/p>\n
While both types are qualified as chase\u00a0aircraft\u00a0for the X-59, each has characteristics that make them\u00a0appropriate for\u00a0certain tasks.\u00a0<\/p>\n
The F\/A-18\u00a0is\u00a0a little more agile flying at lower speeds.\u00a0One of NASA\u2019s F\/A-18s has a two-seat\u00a0cockpit, and the optical quality and field of view of its canopy makes it the preferred\u00a0aircraft\u00a0for Armstrong\u2019s\u00a0in-flight photographers.\u00a0<\/p>\n
At the same time, the F-15 is more capable of keeping pace with the X-59 during supersonic test flights and carries the instrumentation that will measure the X-59\u2019s shock waves.\u00a0<\/p>\n
\u201cThe choice\u00a0for which\u00a0chase aircraft we will use for any given X-59 test flight could go either way depending on other mission\u00a0needs\u00a0and\u00a0if any\u00a0scheduled maintenance\u00a0requires the airplane to be grounded for a while,\u201d Less said.\u00a0<\/p>\n \n