Is Montrose Air Station the most haunted place in Britain?

She, and others, are convinced that it is the spectral epicentre of what is reputed to be the most haunted location in Britain: Montrose Air Station. The poster on the wall suggests that we "Keep Calm and Carry On", but as the former nurse recalls a previous visit, it becomes clear why she might find it difficult to obey the instruction.

"I was in this room on my own in the pitch black," she states, as the bulb above her begins to flicker. "I began to feel a freezing, icy feeling and suddenly I began to make out the shape of a figure sitting in the chair opposite me.

"He was an airman in uniform and when I looked closer I could see that his face was burned. He looked straight at me and said 'Help me. Help me.'"

The apparition vanished but Perks' lingering feeling of unease remains to this day.

However, encounters such as this mean that the paranormal researcher is drawn to Britain's first operational military airfield like a moth to a flame.

The base hit the headlines earlier this year when an ancient Pye wireless, without a plug or batteries, apparently crackled into life and started playing the hits of Glenn Miller and Winston Churchill's speeches.

An internal inspection of the radio revealed nothing more remarkable than a collection of cobwebs and atrophied spiders.

Less well known, but more chilling, is the disconnected phone in the Commanding Officer's room, which is said to be heard ringing late at night. One volunteer, Ian Robb, claims to have picked up the receiver on one occasion and heard a faint, but plaintive, voice calling for help.

Earlier in the day, my request to make a nocturnal visit, to see if I could spend a night braving the ghosts of the 2,000 men and women based here during the First and Second World Wars, was met with a positive response and an additional, unexpected note of caution.

"There's something wrong with this place," warned the lugubrious voice on the other end of the line.As such, it was not without trepidation that I arrived in the Angus town and went to meet my host Perks.

I half-expected the supernatural enthusiast, who claims to possess psychic abilities, to resemble Tangina Barrons, the wizened and diminutive medium from Steven Spielberg's Poltergeist, so I was relieved when a smiling forty-something woman in a sweatshirt shook my hand.

Back at her suburban home, where a statue of Buddha sits serenely outside, Perks plays me a message from her slightly grumpy-sounding grandfather. So far, so mundane until she explains that her grandad passed away some time ago.

Perks, like the character played by Haley Joel Osment in The Sixth Sense, sees dead people - or at least claims to. Not only that but she hears them, occasionally feels them and spends her free time trying to record and film them.

As a seven-year-old in a Manchester motel she heard the frantic scratching and meowing of a cat, which turned out not to be there - no matter how many times she checked behind the door.

"That was the moment I realised I could pick up things that other people couldn't," she says.

Now, as a "sensitive" or "psychic" Perks sometimes struggles to sleep because of the babble of voices coming from "the other side". "I sometimes have to tell them to shut up or get out of the room."

She believes that spirits of departed family members often visit her house and plays me a clip of a gruff voice booming 'Hello!' through her computer speakers. She identifies it as a posthumous greeting from her grandfather.

"He used to answer the phone really loudly, just like that," she smiles. "He was a Fifer and had a quite strong, deep voice."

As dusk turns to twilight the founder of the Circle ITC (Instrumental Trans Communication) Group, which boasts nearly 200 online members, drives me to the nearby air base, which is now a popular visitor attraction.

Over the sound of Native American chanting Perks nods in the direction of the barbed-wire-enclosed airfield, which under the cover of dark, looks more like a prison camp.

"I've been in there so many times, but I would never, ever go on my own," she states ominously.

The country's first military aviation base was set up by the Royal Flying Corps 97 years ago. The coastal runway and the buildings that surround it have been the focus of spectral sightings and claims of supernatural phenomena ever since a young pilot, Lieutenant Desmond Arthur, was killed in 1913 when his biplane crashed at nearby Lunan Bay.

The apparently paranormal happenings are even noted in the station's official records. In the early 1940s, Squadron Leader Ovenden reported being confronted by two ashen-faced airmen who interrupted his "pre-sleep cup of tea".

He wrote: "They asked me who had been in the crash. I told them there had been no crash. They were incredulous because both had seen a plane take off, catch fire and crash into the sand dunes.They were absolutely convinced - I can vouch for these facts."

Rumours spread that they had witnessed a phantom recreation of a fatal accident which had taken place in 1917.

While Perks is a true believer, fellow paranormal and aviation enthusiast, Forbes Inglis, who has joined our vigil, is more circumspect about the prospect of encountering any ghostly inhabitants.

"I suspect there might be something, but I've never had a positive paranormal experience - or at least a direct experience," he says. "I have felt that there was someone else there - and heard what definitely sounded like footsteps - when there wasn't anyone in the place."

After a formidable lock is removed the main door of the visitor centre creaks open and a jowly, impassive face stares back at us. It's a propaganda poster of Winston Churchill in full bulldog mode, urging his countryman to "Deserve Victory!"

Along the corridor, airmen's overcoats and hats hang eerily from pegs, creating the impression that their owners may rush to collect them at any moment.

Forbes, an avuncular figure with a neatly trimmed beard and a knack for storytelling, leads us through the gloom past an extraordinary collection of artefacts, including a piece of the Red Baron's triplane, a warrant signed by Churchill and a silk scarf that belonged to war hero Major James McCudden.

As shadows stretch and floorboards creak he tells of a woman who left the centre's video room heaping praise on a gallant young servicemen who gave up his seat for her.

Not only was there no such airman, but the dearth of flesh-and-blood visitors that day meant there should have been no shortage of seats. "Aye, you get a better class of ghost here," he says, with a twinkle in his eye.

The local historian and author insists that most people who report sightings are down-to-earth, credible and rational. "They most certainly hadn't been smoking something, popping pills or partaking of gin."

Even the kitchen, it seems, is not exempt from ghostly activity. Perks says: "I was washing the dishes one day when the back of my neck started to tingle and I knew there was someone standing right behind me.

"I knew if I turned round I would be looking into the face of whoever, or whatever, was there. But I was so scared that I just froze until I felt that it had left."

Outside, Perks tells how a guttural moaning sound, which she claims to have caught on tape, sent her - and two companions - running in terror from a darkened hangar.

"My husband laughs because I won't even watch horror movies or anything like that. I can be quite a scaredy-cat. People often ask why I do the research if it frightens me and the simple answer is that I want to find evidence of life after death."

After hours pass with not so much of a waft of decades-old Brylcreem we decided to call it a night. With doors bolted we retreat to the control cabin where CCTV cameras keep a silent vigil over each room.For the first time Perks' face lights up with excitement as she points at the screen: "Look at the orbs".

Sure enough, tiny spherical specks can be seen drifting to and fro through the gloom of the CO's office.

Regardless of whether they were dust particles, bugs or restless spirits, Perks is convinced that no one is truly alone when they visit this remarkable monument to human bravery and bloodshed.

Last month John Melville, a much-loved station trustee, opened the gates and allowed her and some colleagues to carry out overnight paranormal research. He passed away suddenly in recent weeks, yet Perks has no hesitation in placing a report of the vigil into his office pigeonhole.

She says with a smile: "John loved this place and is still very much part of the Station. He wouldn't want to miss out on anything and will continue to be here with us."

If the dozens of eyewitness are to be believed, he'll be in good company.