SQL Server 2019

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CREATE TABLE flight (
  src CHAR(3)
, dest CHAR(3)
, stt DATETIME
, endt DATETIME);

INSERT INTO flight VALUES 
('MSP', 'SLC', '2022-10-02 11:45:00', '2022-10-02 14:10:00'),
('SLC', 'LAX', '2022-10-02 15:20:00', '2022-10-02 17:45:00'),
('MSP', 'LAX', '2022-10-02 12:15:00', '2022-10-02 15:05:00')
3 rows affected

WITH flight_paths (src, flights, path, dest, stt, endt) AS (

SELECT
  src
, CAST('["' + src + '-' + dest +'"]' AS nvarchar(max))
, CAST('["' + src +'"]' AS nvarchar(max))
, dest 
, stt
, endt
FROM flight

UNION ALL

SELECT
  fp.src
, JSON_MODIFY(fp.flights, 'append $', f.src + '-' + f.dest)
, JSON_MODIFY(fp.path, 'append $', f.src)
, f.dest
, fp.stt
, f.endt
FROM flight f
JOIN flight_paths fp ON f.src = fp.dest AND f.dest <> fp.src
WHERE EXISTS (SELECT 1
    FROM OPENJSON(fp.path) arr
    WHERE arr.value NOT IN(f.src, 'LAX')
  )
  AND f.stt > fp.endt

) 
SELECT flights, stt, endt, path stopovers
FROM flight_paths
WHERE src = 'MSP'
  AND dest = 'LAX';


flights
stt
endt
stopovers


["MSP-LAX"]
2022-10-02 12:15:00.000
2022-10-02 15:05:00.000
["MSP"]

["MSP-SLC","SLC-LAX"]
2022-10-02 11:45:00.000
2022-10-02 17:45:00.000
["MSP","SLC"]


WITH flight_paths (src, flights, path, dest, stt, endt) AS (

SELECT
  src
, CAST('["' + src + '-' + dest +'"]' AS nvarchar(max))
, CAST('["' + src +'"]' AS nvarchar(max))
, dest 
, stt
, endt
FROM flight
WHERE src = 'MSP'

UNION ALL

SELECT
  fp.src
, JSON_MODIFY(fp.flights, 'append $', f.src + '-' + f.dest)
, JSON_MODIFY(fp.path, 'append $', f.src)
, f.dest
, fp.stt
, f.endt
FROM flight f
JOIN flight_paths fp ON f.src = fp.dest AND f.dest <> fp.src
  AND fp.dest <> 'LAX'
WHERE EXISTS (SELECT 1
    FROM OPENJSON(fp.path) arr
    WHERE arr.value <> f.src
  )
  AND f.stt > fp.endt

) 
SELECT flights, stt, endt, path stopovers
FROM flight_paths
WHERE dest = 'LAX';


flights
stt
endt
stopovers


["MSP-LAX"]
2022-10-02 12:15:00.000
2022-10-02 15:05:00.000
["MSP"]

["MSP-SLC","SLC-LAX"]
2022-10-02 11:45:00.000
2022-10-02 17:45:00.000
["MSP","SLC"]

flights	stt	endt	stopovers
["MSP-LAX"]	2022-10-02 12:15:00.000	2022-10-02 15:05:00.000	["MSP"]
["MSP-SLC","SLC-LAX"]	2022-10-02 11:45:00.000	2022-10-02 17:45:00.000	["MSP","SLC"]