The HW5 file series (continued)

Codes within codes

You thought the Luftwaffe wrote its messages in plain language? It seems that as the war went on they introduced codewords for more and more things. Some are well known, like Ahorn (maple) for Me 262 — except that it originally meant Fw 190, the change confusing the Allies for a while. The Fw 190 became Dahlie (dahlia) and the Bf 109 Farn (fern). Zinn (tin) was the Ar 234; the Me 262 was Silber (silver); and the Jumo 004 engine was Orkan (hurricane).

Happily, all these are explained whenever they occur and the same is true for the nonsense words used for the various levels of command right down to Staffel level. Examples include:

ABIOC = JG

KABUS = I./KG

NABEF = II./NJG

NABEF = II./NJG

ZANET = IV./ZG

AKERA = 12./JG

KEKOD = 7./KG

NATOI = 6./NJG

BESAD = 9./SG

ZEAKE = 1./ZG

UDASO = NAG

UBERO = FAG

GABOF = OKL

GAMXE = Luftlotte 6

GAMXE = Luftlotte 6

GENOM = Fliegerdivision

GEPAX = Flak Div.

The misuse of these codes explains some of the oddities in DEFE3, where what you know must be a 2. Staffel is given as a II. Gruppe: whoever compiled the original message picked ABUNO from the list instead of ADIFA.

While the meaning of many of these can be inferred from the context (ABOPA 26 with the Fw 190 D-9 is pretty obviously I./JG 26) and initial letters are a giveaway (A always means fighters etc.) the Allies’ ability translate whatever came their way suggests they’d got hold of the whole list from somewhere. German grammar undermined security somewhat because German nouns have genders and these modify any associated articles and adjectives: a Geschwader for example is neuter, while a Staffel or Gruppe is feminine. Then again, perhaps the object was not primarily security but abbreviation. There were however problems for the Allies, as advised by Bletchley Park on 29 July 1944:

The greatest difficulty in interpreting covernames of the type KEPAD, KEDNI etc. lies in the fact that they are imperfectly understood by the Germans themselves and consequently used wrong [sic]. Thus they constantly confuse the Staffel number with the Geschwader number, or with the Gruppe number. It thus becomes necessay in each text to consider (A) what the covernames should mean (B) what in this particular context [they] are meant to mean …

The chances of these names being used wrong remains [sic] so high that even if the right meaning is established the new context must still be watched to see if a wrong meaning is not intended.

Where it all goes bad is when they start using code words for numbers, right up to three-digit ones. The cryptanalysts understood some of these but not others — rendering useless (to me) a list of replacement Ar 234s taken over by III./KG 76 and leaving a measure of uncertainty over dates and times of day in some messages. The basis of the system is clear at least: groups denoting numbers begin with a Z (for Zahl = number); dates begin with a T (for Tag = day, or Termin = date); times begin with a U (for Uhr = hour). Then each group will follow in alphabetical order, for example:

TAWBU = 26 March

TAWID = 27 March

TAWOJ = 28 March

TAWTY = 30 March

ZACBU = 106

ZACGI = 107

ZACID = 108

ZANE = 109

Since with sufficient examples this system is easily broken, it may be that again this was more about ensuring quick and unambiguous transmission than security.

In the final weeks of the war a new set of code groups for units was introduced, examples including: BIVAB = II./JG; ETMOB = 2./NAG; HUKHI = I./NJG; SOJGU = II./KG. The new system seems to have run alongside the old and its introduction may not have been completed prior to the German surrender.

Many formations are referred to by what I imagine were regular callsigns (Luftflotte 1 was Standarte for example) but almost all of these are explained, leaving only the occasional “not known.”

continued on next page …

navtag

ultraplate Next Top Back HW11link furtherlink HW5link HW1link AIR40link DEFE3link whatlink introlink homelink