Upon further review, I don't see any direct conflict with the safety code.
Take a two stage two engine cluster (4 engines total). Worse case scenario: One engine lights on launch; the rocket cocks because of off- center thrust and this problem compounds when the 2nd stage fires. Potentially, the rocket could be pointed toward the ground when the 2nd stage fires. I expect this probability of this occurring would increase with an increase in the number of motor used. Maybe not a safety code violation, but a potentially dangerous situation that would be hard to mitigate (?)
Last time I launched a 2 "C" engine cluster, I overheard, "A 'D', the hard way." LOL
Take a two stage two engine cluster (4 engines total). Worse case scenario: One engine lights on launch; the rocket cocks because of off- center thrust and this problem compounds when the 2nd stage fires. Potentially, the rocket could be pointed toward the ground when the 2nd stage fires. I expect this probability of this occurring would increase with an increase in the number of motor used. Maybe not a safety code violation, but a potentially dangerous situation that would be hard to mitigate (?)
Last time I launched a 2 "C" engine cluster, I overheard, "A 'D', the hard way." LOL