From Halopedia, the Halo wiki
The Nandaos are described as having a "dart shape", and are considered powerful enough that an understaffed Covenant frigate would avoid having to face a squadron of them. The craft are capable of flying at Mach 12 and are optimised for swift, aggressive attack runs.
The F-29 Nandao emerged in the early years of the Human-Covenant War as the UNSC's premiere A/X strikecraft, and was often deployed in large numbers and at extraordinary speeds to overwhelm and neutralise Covenant forces before they could organise an effective response.
A squadron of Nandaos was also in service as part of the complement of UNSC Spirit of Fire, and was in use by the time of the ship's participation in a conflict against the Banished on Installation 00, in 2559. The Nandaos were employed as escorts for wings of Shortsword bombers. By this time, the Nandao was considered outdated. Nonetheless, its success against Covenant strikecraft ensures it is still one of the UNSC's primary interceptor solutions.
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