I was listening to some of the old FDNY radio traffic on Hartford Fire Department radio ( http://hfdradio.com/FDNY.htm ) which is a great site. One of the runs I remember was a multiple in Coney Island which turned out to be a dispatcher's 4th alarm. Rescue 2 was assigned - on the 3rd alarm. There was no Rescue 5 (SI) yet. I know Rescue 2 was very busy, but it does seem to be very conservative to wait until the 3rd would be transmitted to start a Rescue for a multiple alarm structure fire. This was a 2nd on arrival and the chief requested Rescue 2 on the 2nd because there were so many occupants being removed.
The 8th division in SI did not respond to Brooklyn back then. Since the 12th Division was unavailable, the covering deputy came from either the 10th or 11th Division, a very, very long run. It does not make any sense that the 8th Division never left SI back then. The bridge was up. What was the logic?
On 10-75's in many parts of the city, there were no 4th engines, no Rescues, no Squads. And no FAST trucks yet. I believe the field comms went on all hands - doubtful fires. I think you had 3 or 4 engines, 2 trucks, 2 BCs and 1 deputy with the field comm (if available) for all hands, another 3 engines and a truck on the 2nd. The 3rd added 3 more engines, another truck and a BC for communications coordinator. (I might have missed a unit or two.) But a 3rd alarm in some parts of the city had maybe 9 or 10 engines, 4 trucks, a Rescue (if available), 3 BCs, a Deputy and a field comm unit. That seems to be equivalent to a 2nd alarm assignment today. It is hard to compare.
I remember being told by a chief that in that part of Brooklyn (Coney Island), all hands - doubtful (7-5 signal) transmissions automatically were upgraded to 2nd alarms because it took so long to to get multiple alarm units to respond in. Was that unique to Coney Island? It would seem other outlying areas (Far Rockaway, City Island) would be similar.
There are also examples of units using the 10-30 (working fire) radio code. This was another thing I do not understand. Did it ever really work - trying to have the first due units differentiate between a 10-30 fire (2 & 2) or a 10-75 fire (3 & 2 or 4 & 2)? Many times, the engine used a 10-30 and the 1st due truck used the 10-75 (or vice versa). Why wasn't the 10-30 code eliminated years sooner?