Rotation of aircraft

**78SqnHistory** · 26th August 2012, 19:25

This weekend I have been creating a database of all operations completed for each aircraft (by serial number) that operated with 78 Sqn and it started me thinking how were aircraft rotated from front line Sqns to training units, salvage units etc. I know that aircraft would be rotated when a better type became available e.g. Whitley to Halifax and obviously aircraft joined Sqns to replace those lost on operations and in trg accidents. But how were aircraft selected to be removed from frontline service, was it purely on the amount of hours flown? On 78 Sqn there doesnt seem to be any pattern.

Rgds
Daz

**Oldduffer** · 26th August 2012, 20:10

Daz,

I think your last sentence is probably closer to the truth than might at first seem plausible.

Aircraft maintenance was not an exact science by any means, although maintenance 'intervals' were specified. In wartime, the added components were the loss of an aircraft and the physical damage which could be inflicted on an aircraft which returned from operations and which required to be repaired before the aircraft could continue in use.

Some damage eg patching holes in the skins, replacing engines without colateral damage, could be done at unit level and reasonably quickly but other damage would require the aircraft to be sent away to a specialist repair facility. In some cases the aircraft might be flown away but in others it might have to be broken down (hence, something called the 'transportation joint', where and aircraft could be 'naturally' broken apart).

The practice remains to this day with 'rectification' of faults and 'scheduled' or 'preventive' maintenance being carried out periodically.

Aircraft would be 'handed down' to lower level units when cast off by operational squadrons and the pace of wartime developments meant this was a more rapid process than might otherwise have been the case. Furthermore, new 'Marks' of aircraft appeared fairly regularly, whereas now the air vehicle is lilkely to be enhanced and updated rather than physically replaced by a newer version.

I have heard it said that some bomber types were manufactured against standards of construction which actually assumed that they would not or were unlikely to reach a stage where deep maintenance was required. Basically, aircraft became obsolete or obsolescent, more rapidly. Of course, at the war's end some aircraft were flown direct from the manufacturer to a salvage unit where they were immediately broken up and smelted down (Halifax at Childs Ercal). The rationale here being that you couldn't just stop all production without crippling the manufacturer

May I suggest that you accept that logic was not the prime driver in this process and for every example you can cite for one course of action, there will be a contra example! One could lose an awful lot of sleep, I feel, trying to ascribe any rules to the process!

Colin Cummings

**Graham Boak** · 26th August 2012, 20:16

The first answer is after achieving the number of flying hours permitted before major overhaul. I'm sorry, I don't know what this number was. Perhaps a (too) obvious question, but do you have an account of all the non-operational hours flown by each aircraft?

The second answer is after suffering greater damage than can be repaired on site. Either by enemy action or inadvertent mishandling.

The third possibility is if the aircraft developed some kind of performance or handling problem that the squadron couldn't solve.

A fourth possibility is if the aircraft fit became too outdated and it was simpler to transfer it out than bring it up to date.

Others may have additional suggestions.

**78SqnHistory** · 26th August 2012, 20:40

Thank you both for your replies. Just wondered if there was an actual policy or if the decision was left to the Sqn.

thanks again

Daz

**David Duxbury** · 26th August 2012, 23:04

Decision as to future of any aircraft on a particular station was probably the responsibility of the senior engineer officer on the station, although it may have been undertaken at squadron level prewar. Remember that during most of WW2, squadrons of Bomber Command did not have a full ground staff as was the case prewar, and typically this was sufficient for normal servicing - refuelling, bombing up and arming, tyre pressures, oxygen systems, any other reservoirs requiring "topping up", electrical accumulators (batteries), numerous minor adjustments, changing over of radio equipment that was causing problems or required modification, perhaps also instruments, but very little else. Others will correct me if I am wrong, but I believe that even prewar there was, as part of the station establishment (and NOT the squadron's) a sub-unit known as Station Workshops, which undertook more serious work on (mostly) airframes, possibly also on engines, and this process probably only accelerated during the war, with the increase in tempo of operations, etc. Station Workshops traditionally had mostly tradesmen of the Fitter (advanced) variety, with far fewer of the entry level tradesmen.
There would have been guidelines (a criteria) on assessing the desirability of maintaining any particular aircraft on full operational duty, probably set at Command level, and would depend on whether a particular model or mark of aircraft was becoming a bit long in the tooth (and nominally superior models were being allotted to squadrons), or those NOT fitted with some type of equipment now thought important were becoming an operational risk, or if some undesirable feature in any type was becoming burdensome on maintenance staff or in an operational sense, then stations (later bases) might be asked to select aircraft to be removed from frontline service, and in which order, as no doubt it was the stations or bases which had full access to the aircraft's servicing records, flying hours, time to major inspection, engine hours, and general overall condition as well as the exact equipment fit.
The allotment of aircraft in the RAF was a serious business and selection of aircraft for removal from front-line service was probably undertaken at station or base level but using criteria set at Command level, with the actual allotments being generated by the special section of Air Ministry which was charged with this work; allotment action would specify the particualr aircraft, and order it to be transferred to another unit, and normally the timing of the transfer was something along the lines of "as soon as possible", at discretion of ferry pilot to a certain extent. As station commanders would not have been keen on having non-operational aircraft cluttering up their airfield, they would probably ensure that aircraft under allotment were speedily sent on their way. My ten cents worth. I often pondered as to why the turnover of heavy bomber aircraft on 75 (NZ) Squadron seemed so high, mainly because no reasons were ever given, so I can understand why an onlooker might be curious. I had the feeling that Stirlings in particular were rather prone to being "sent on their way" with monotonous regularity, but this may being unfair to this type - from memory the equivalent details for Lancaster were not included in squadron records.
David D

**Tony H** · 26th August 2012, 23:52

Buring the midnight oil Daz? Oh for a sight of Ivor Easton's engineering notes to ease your research!

Tony H
78 Sqn

**malcolm_raf** · 27th August 2012, 07:23

Hi David

Before WW2 and the expansion most stations were occupied by a single squadron and hence the personnel on the station were squadron personnel so there was not a separate station workshop. However as the RAF expanded andit became necessary to house more then one squadron on a station, then a separate SHQ was formed but according to the AFLs very few had officers allocated for engineering duties so it seems likely the servicing was still under squadron control

Malcolm

**78SqnHistory** · 27th August 2012, 10:30

David, Malcolm

Thank you

Tony
Yes I was burning the midnight oil, got 1940, 41, 42 and 43 completed so far. I think I will drop Ivor's son another line to see whats going on. I'm waiting for three families who have promised me information at the moment, will let you know how I get on.

Daz