Mr Wain’s pronunciation is phonetically interesting as it includes a lot of those features typical of old-fashioned RP. Notice, for instance, the way he pronounces south in the phrase the south side of the airport. The word sounds something like sɑːθ rather than saʊθ. That is because in our correspondent’s pronunciation the first part of the diphthong aʊ appears to be extra long, with a weak glide probably involving comparatively little raising of the tongue and little lip-rounding, if at all.
Terms like passengers, handy, travellers, scanner, landing, tax (payer), which in current RP normally have æ, are pronounced with ɛə or eə, that is closer varieties of æ, which may sound diphthongal in traditional RP.
Interesting is also the pronunciation of year, more similar to jɜː than to jɪə, and the word tube, which our BBC journalist pronounces as tjuːb first and then with its coalesced form tʃuːb.
Other noticeable features include tɑ̈ːm for taɪm time; the smoothed forms of quiet kwaɪət and hour aʊə, realized as kwaət and ɑə respectively; the ɔː in saw, which sounds slightly more open than usual; and the word formality, pronounced fɔːˈmɛəlɪtɪ, as opposed to today’s fɔːˈmæləti.
Finally, it is also worthwhile noting the term walkways, which has something of a monophthongal ɛː, thus ˈwɔːkwɛːz. In the words motorway and today, though, this realization appears to be less noticeable.
More on classical RP in future posts.