The operation was setup to deter Russian aggression and the RAF is providing a large number of personnel from the 135 Expeditionary Air Wing (EAW) based at RAF Leeming.
As part of the eAP, the RAF sent four Typhoon jets to the Mihail Kogalniceanu airbase - situated just over 1,000km away from Russia on the other side of the Black Sea.
One of the Typhoon pilots, Squadron Leader Ellis Williams, said: "We have an incredibly capable fighter aircraft and we operate here alongside the Romanian Mig 21s and there's a generational gap between the capabilities.
"When we are here we notice a very strong difference in the behaviour of the Russians because we are a strong deterrent."
British personnel to Romania in April for four months as part of Op Biloxi, policing the skies above the Black Sea.
There has been only one scramble when a Russian Federation Air Force IL-20 entered NATO airspace on 4 May - but they practice for a similar event twice a week.
Forces News reporter, James Hirst, visited the RAF crew in Romania to see how they provide the country with Quick Reaction Alert:
Speaking to Forces News in June, Squadron Leader Roger Cruikshank DFC, 2 Squadron said: "We’ve had one live scramble and that was at the beginning of the operation.
"The QRA [Quick Reaction Alert] is there so if any threat aircraft threaten our air space that we are patrolling with the Romanians, then they will launch us to go and intercept that threat aircraft.
"We are there on QRA, on point, ready to deliver that within minutes.
"We are there to deter that threat as well, just from being airbourne, and because we are flying most days that means we are always delivering that presence alongside our MiG-21s - the Romanian counterparts."
Watch the full interview with Squadron Leader Roger Cruikshank on what it is like to be scrambled:
Asked whether his squadron is fully resourced despite a reported funding battle between the Prime Minister and the Defence Secretary back in the UK, Wing Commander Chris Ball said: "We have everything we need to conduct this mission, so I've got no concerns with that.
"Of course, as a military commander, we've got a lot of great ideas as a team and we want to push hard and make good use of those resources and squeeze as much out of our time here as possible.
"I think we are getting great value out of this mission because, you could ask, why are we air-policing Romania? Well, we are demonstrating we are committed partners within NATO."
Answering questions on a potential Russian threat, Wing Commander Ball said: "Here, ourselves, we don't have a high threat level against us, we are conducting a peace-time defensive operation.
"We are part of that NATO alliance, we would take collective decisions if ever we push towards Article Five - collective defence - so what we are doing here is policing the skies and also taking that opportunity to integrate into NATO, train with our NATO partners, so that we are stronger and more cohesive if ever the need came to take some kind of increased response."
The RAF will carry out its eAP role in Romania until September, when they will hand over to Canada.
The RAF is then expected to deploy to Iceland and Estonia in the next 12 months.