Hi Tim,

Old Sarum changed to an 8.33 frequency 123.205 in October.  There was a Skywise alert that the frequency had changed.  The frequency cards on the AIS website have changed but the aerodrome entry in the AIP has not.  As a result SD has the old frequency as published.

I spoke to the CAA person in charge of rolling out 8.33 and said they were mad to allocate 8.33 frequencies before the legal date because that just invites people with 25kHz radios to use them on 8.33 channels.  And if they are allowed to do it there how are they to know not to do it elsewhere too. And having a mismatch in the AIS system is careless.

I spoke to the FISO at OS who said they had indeed changed to an 8.33 frequency early because that reduces their licence fee to 1/3 of the previous cost.

I believe there is an 8.33 roll out plan but if they go on like this ‌people who rely on SD and indeed the UK AIP are going to end up on the wrong frequency or blocking an adjacent one.

John‌‌

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Hopefully Old Sarum will be one of a very small number of stations making the decision to move to 8.33 before aircraft are required to be able to address the new channel correctly, and I suspect (but don't quote me) that the enforcement teams will turn a blind eye to such behaviour for another four-and-a-bit weeks. Indeed the conspiracist in me believes that the early publication via the AIS website may even be accidental.

‌‌I would expect the AIP (and therefore SD) to be updated on the first update cycle post January 1st, whereupon all aircraft are legally required to have 8.33 compatible radios if they wish to communicate with ground stations which have been allocated 8.33 channels. NORDO is the only other legal option, as dialling up 123.20kHz on a 25kHz radio when 123.205 is the published channel will be illegal, after more than a decade of warnings. Remember also that the deadline for ground stations (other than a very small number with exemptions) to be 8.33 compliant is only 12 months away, and even the exemptions expire within the very foreseeable future.

I understand the problem but we need to keep our airfield data matching the official AIP. So it's the CAA who need to be encouraged.