[28, 1564, 80412, 145948, 231964, 234524]
0x1c 0x61c 0x13a1c 0x23a1c 0x38a1c 0x3941c 

6 blocks:

1: @28
52 blocks each 29 bytes long?

2: @1564
offset 0x1C:
52 blocks with 29 bytes length each?
offset 0x61C (1564):
52 blocks each 77 bytes = 4004 bytes length

offset 0x15C0 (5568):
52 blocks each 17 bytes = 924 bytes length

offset 0x195C (6492):
nav point descriptions (Tiger's Claw, Nav1, Asteroid, ...)
52 blocks each 77 bytes = 64064 bytes length

3: @80412
52 blocks each 78 bytes. 
contains hardly any data.

84508: nav point notes.
64 bytes each navpoint note. 16 navpoints for 52 missions = 53248 bytes length
nav point notes should end at 137760



4: @145948
size would make for 52 blocks with 1654 bytes each.
however, I'm quite sure that there are several sub-blocks.

5: @231964
difficulty, wing names
skips first four entries and starts wing names at 232124


6: @234524
starts at 0x3941C (234524)
system names, 40 characters fixed
1st at 0x39444 (234564)

first one is always squadron (wc1, sm1, sm2)
last two of wc1 begin with - (invisibility toggle?)