Rod and Doreen Evers and their friends Malcolm and Ann Longden were on their way to a cruise around the Caribbean when their British Airways flight to JFK was evacuated on the runway at Heathrow after a Stanley knife with a retractable blade was found wrapped in a blanket on Malcolm's seat.
The friends say they were concerned at such a blatant breach of airport security and were promised a full report from British Airways on their return. But so far they have heard nothing.
Mr and Mrs Evers, who live in Old Town, told the Herald, "In this day and age it is frightening to think a knife could have made its way on to a plane. We want to know how it happened."
The drama began when the couple and Mr and Mrs Longden, who live in Lancashire, boarded flight BA117 on the morning of April 6. They were heading to JFK in New York for a connecting flight to San Juan where they were due to spend a night in a five star luxury hotel before boarding the cruise liner, Galaxy, to celebrate the Evers' wedding anniversary.
Mr Evers, a former police officer, said, "We were just settling into our seats when Malcolm said to me, 'Take a look at this'. To our horror, there was an industrial type Stanley knife inside the sealed polythene blanket bag sitting on top of the blanket."
The package was handed to cabin crew but while senior officers and the captain were being informed, the drama took another twist when someone knocked on the plane's rear door saying they had hot food to deliver.
The delivery man was turned away but the friends say they were concerned as the aircraft was fully loaded and they fear it could have been connected with the knife and an attempted terrorist attack.
All the passengers and crew were asked to leave the plane and after further security checks, were allowed to reboard.
Mr Evers said, "You can imagine our anxiety levels rising, especially when we were asked to keep quiet about the incident and tell no-one. Sparse information was given to the passengers on the flight and we tried to remain calm.
"The captain thanked us for acting so swiftly, urged us to remain quiet about what had been found, gave us a bottle of Bollinger champagne, assured us we would get a full written report of the findings of the investigation and told us he had called ahead to JFK to re-book a new flight to San Juan for us that evening.
"We had pre-booked a night at the Sheraton Hotel with a tour around the city the following day before we transferred to our cruise ship. Imagine our sheer disbelief when we landed at JFK when, after an hour or more of total disorganisation, and having seen many families
from our flight handed their re-booked flight tickets for that evening to San Juan, we were told we would be staying the night in a hotel and not travelling on to San Juan until the following morning!"
The friends spent two weeks travelling round the Caribbean islands stopping at Grenada, Barbados, Dominica and St Lucia. But on their return journey home, their suitcases were delayed and did not arrive until two days later.
Both the Evers and Longdens have written to BA asking for the outcome of the investigation and answers to questions, but say that apart from a 'derisory' note apologising for the delay, their questions still remain unanswered.
"Where did the knife come from?," said Mr Evers. "Was this a pure accident? If so, how come it escaped BA's flight security so easily? Are there now systems in place to avoid this situation in the future? How come an airport operative could approach the back door of an aircraft with hot food when it was already loaded, secure and waiting to leave? Was this reported by cabin crew and what were the findings?"
Mrs Evers, a teacher at Willingdon School, added, "We are glad they acted so quickly when the knife was found but we are bothered they have not let us know what it was all about."
A spokesperson for British Airways said, "We take any security breach extremely seriously and investigate it as a matter of priority.
"In immediate response to the situation the aircraft and all passengers and crew were re-screened before the flight was cleared to continue to ensure its safety.
"In an additional step, all blankets were removed from the aircraft and replaced with new ones.
"We apologise for the disruption this caused.
"The incident has been fully investigated and concluded.
"It was discovered that this was a one-off incident and steps have been put in place to avoid this type of incident in the future."