[6][1] The Burner 2 used with the Thor-Burner was the first solid fuel upper-stage vehicle used for general space applications that had full control and guidance capability.

[11][1][7] On February 19, 1976, the attempted launch of a DMSP satellite from Vandenberg's SLC-10W went awry when SECO occurred 5 seconds early.

[12] Although the second stage separated and fired properly, the satellite was left in an unusable orbit from which it decayed only one hour after launch.

Investigation into the mishap found that the Thor had been loaded an insufficient amount of RJ-1 (a higher grade of kerosene fuel that offered enhanced performance over standard RP-1) for the mission.

However, the postflight investigation also found that, even if the correct propellant load had been carried, the mission would have still failed because the Thor did not have sufficient performance to loft the DMSP into the required orbit.