Although, another space to consider would be the larger landscape advert projections on the actual platforms.
I have found the best source of information to be from http://www.transportmedia.co.uk/london-tube-underground-advertising
Variations of screen advertising on the tube.
My original idea of the digital escalator panels would work quite nicely, they are short and require no sound.
The cross track projection could work really well, as it gives the opportunity to plan what time of day the ad is shown. Especially for this project the target audience is key, timing the ad at peak times could target workers that live in London, as opposed to tourists on weekends and during the day.
Although this website was helpful, it didn't offer any information in terms of timing and dimensions of the ad spaces. It also specifically outlines on the website that they do not want to be contacted by students wanting information for research... gutted.
This video gives me an idea of different ways I could use the ad space, like spreading the animation across more than one panel. It also gives me a better idea of how long the animations should last for.
I have found an article, which includes information saying that the time slots sold for the escalator ads are 5 or 10 seconds.
London Underground to host digital advertising for the first time
LONDON - The London Underground is to allow digital advertising on its escalators for the first time, as part of a trial being handled by Viacom Outdoor.
Viacom, the current holder of London Underground's outdoor advertising contract, is trialling the display screens, called Digital Escalator Panels (D-EPs), on the side of the most-used escalators on the network at Tottenham Court Road station.
While including moving images and text, the 66 panels involved in the trial will not involve TV or film advertising on safety grounds for fear of distracting travellers.
The screens also have the ability to link up, making the transfer of images from screen to screen possible. It also gives clients the option of time-specific advertising, such as theatres using evening slots.
Viacom is selling five- and 10-second slots and has seven clients, including London Underground, already lined up.
The trial is due to start within months, according to a spokeswoman, and if successful will be rolled out at other locations across the network.
Jon Lewen, Viacom Outdoor's digital account director, said: "We are committed to exploring new and innovative ways to capture and captivate London Underground users. DE-Ps will both enhance the consumer's experience of advertising on the Tube and offer revolutionary new creative opportunities for our clients to connect with this audience in a more creative and tactical fashion."
Meanwhile, London Underground is this year conducting a regular review of its outdoor advertising account, with a new list of bidders for the £75m a year contract set to be released within days.
Last month, Viacom won the rights to sell space across Tyne and Wear Metro's 57 stations. The firm beat Maiden, JCDecaux and Primesight to win the contract, worth £10m over five years.
Some statistics concerning tube advertising.
Advertising in this unique environment not only allows advertisers to broadcast their message to everyone, it also offers a unique level of consumer engagement. With an average of 3 minutes waiting time on platforms, commuters have plenty of time to read, consider and take in your message. Moreover, 87% of consumers welcome Tube advertising as it provides a welcome distraction during their journey.
All in all, the positive relationship consumers have with Tube advertising leads them to act on it. Our research shows that 79% of commuters have been somewhere, bought something or looked something up as a direct result of tube advertising.
Finally found the dimensions!
So, the animation needs to be 419mm by 572 mm (portrait) and either five or ten seconds long. Taking into consideration that it can be spread across more than one panel.