Bit of a Fender Bender at Dublin Airport
You may remember my post about a previous incident at Dublin Airport, also involving Ryanair: Fear of Landing – “Where’s that Guy Going?” Runway Incursion at Dublin
That was the case where a Monarch crew took a wrong turn and blundered onto the active runway — right into the path of a Ryanair 737 on its take-off run. The Ryanair Captain initiated a high speed rejected take-off at 124 knots. By the time the Air Traffic Controller realised what was happening and shouted at the Ryanair to stop, the First Officer responded, we’re stopped. The Ryanair flight returned to the stand to have its brakes inspected. Meanwhile, the Monarch flight continued on its way, taking off three minutes later. That’s probably the first time ever I’ve felt sorry for a Ryanair flight for being late.
Anyway, Dublin airport has hit the news again, this time for two Ryanair aircraft damaged during taxi.
Stuck on a @Ryanair plane @DublinAirport clashed with another plane en route to runway – lost top of our wing! pic.twitter.com/uxVlTG84cX
— Emily Carroll (@EmzCarr) October 7, 2014
The Daily Mail ran the story with a typically staid headline:
Passengers watch in horror as two Ryanair planes collide on Dublin Airport runway
The Evening Standard followed suit:
Passengers watched in terror as two Ryanair planes crashed into each other on the runway at Dublin airport.
Quick point: neither aircraft was actually on a runway. The first aircraft was holding short of the runway and the second aircraft was behind it.
Ryanair, on the other hand, referred to the ground incident as a “scrape”. A notice was posted onto their website that afternoon with the following statement:
Two of our aircraft were taxiing slowly to the runway at Dublin Airport this morning. The winglet of one aircraft appears to have scraped the tail of the other. Both aircraft were under the instruction of Dublin Airport Air Traffic Control at the time.
There was no impact on customers on board and Ryanair contacted the IAA and worked with them to return both aircraft to stand. Affected customers disembarked, were provided with refreshment vouchers and boarded two replacement aircraft, which departed to Brussels Charleroi and Edinburgh later this morning.
The notice has since been deleted from the site.
The winglet or sharklet extends above and more recently also below the wing at the wingtip. They increase the performance for jets by reducing drag, which can mean a higher cruise speed or more commonly, better fuel efficiency.
How Things Work: Winglets | Flight Today | Air & Space Magazine
Winglets reduce wingtip vortices, the twin tornados formed by the difference between the pressure on the upper surface of an airplane’s wing and that on the lower surface. High pressure on the lower surface creates a natural airflow that makes its way to the wingtip and curls upward around it. When flow around the wingtips streams out behind the airplane, a vortex is formed. These twisters represent an energy loss and are strong enough to flip airplanes that blunder into them.
But obviously the winglet isn’t going to survive impact with another aircraft’s tail. This photo taken by Niall Carson makes it look a bit more than a scrape, I have to admit.
Irish newspaper accounts of the passengers show that they were somewhat bemused but not actually watching in horror or terror.
Dramatic picture shows wing tip embedded in plane after two Ryanair jets collide – Independent.ie
Andrea Cunningham, from Drogheda, was due to fly to Edinburgh for a job interview this morning and was a passenger on one of the Ryanair aircraft.
Speaking on RTE’s Morning Ireland programme, Ms Cunningham said the impact was minimal, but the plane shook.
“We just kind of turned a corner and hit into another plane.
“It wasn’t a huge impact to be honest but you could see the plane shook and then it kind of just stopped.
“We were on the plane for about an hour, maybe short of an hour.
“We were just waiting to go back into the airport terminal,” she said.
It seems that visibility was poor and one aircraft was passing behind without quite enough space there. The ATC recordings make it clear that the flight crews involved were really not sure what happened in the moment. Note: if you are reading this from the mailing list, you may need to click through to get the audio file.
This photo, which I was unable to find an attribution for, gives good context for how it happened.
According to a poster on the Professional Pilots Rumour Network, this was an accident waiting to happen.
Dublin: 2 x RYR in contact during taxi. Both damaged.
I retired some years ago from 50 years of professional (accident free) flying and I was very familiar with Dublin Airport.
I am quite sure that dozens of us were aware that the south east corner of that airfield, after they built runway 28, was an accident waiting to happen. To say that this little corner, even on a CAVOK day, is busy, is an understatement.
In fact, I have just downloaded an IAA Aerodrome Chart (EIDW AD 2.24-1) which has, at the top left hand corner, an insert diagram entitled (in red) “Runway Incursion Hot Spots”. This shows the problem beautifully.
In the morning nowadays, departures are made from runway 28 and 34 simultaneously so that part of the airfield can get quite congested. If you want my opinion (and you probably don’t) my guess is that the aircraft holding short of 28 was being super-safe and holding back a bit further than normal. The aircraft heading for 34 tried to taxi past but mis-judged his wing tip clearance by about 10 feet.
Now, as an ex-DC-10 captain, I need to tell the great unwashed on this thread that it is quite impossible from the flight deck to judge where your wing tip is within 30 feet or so (see BA 744 at JNB).
My car beeps loudly when I’m backing up into something else, maybe the wing tips need similar sensors? It would at least make for some amusement.
Another excellent article. I also have been based at Dublin Airport. Like the pilot you quoted, I retired from flying after (nearly) 50 years accident-free flying, albeit on smaller aircraft (the largest one I flew was the BAC 1-11). I have not downloaded an airport chart from the AIP or Jeppesen, but I agree with everything.
Having said that, I have to qualify:
“Passengers watch in horror”? Probably due to missed appointments, nobody was in any danger. It was, as you put it, the aviation equivalent of a “fender bender”, albeit a very expensive one.
But then, any aviation incident, however small, is always exaggerated by the press if it makes a good story (a mentality which now probably forever has saddled us with the misnomer “black box” for a bright orange object).
I have been a Ryanair captain myself and this did not fill me with love for the company ethics.
Although the crew and staff, that must be said, were working together very well.
In the early days, on an office wall was a notice saying “All those not fired with enthusiasm,
Soon will be”. It was only partly in jest.
It is again demonstrated in the quoted press release where Ryanair asserts that “both aircraft were under the instruction of Dublin Airport Air Traffic Control at the time”.
Which is a white lie.
OK, ground control is part of the ATC system but under condition of good visibility pilots are only instructed about the taxi route and where to hold clear (of runways and other potential spots of conflict).
ATC may, if “low-vis procedures are in progress” assume a higher level of control over ground movements, but under the conditions this incident took place the separation between taxiing aircraft (other than the instructions about taxi routes and holding points) was entirely the pilots’ responsibility.
The wording of Ryanair’s statement is suggestive of a wrongdoing or at least some shared responsibility from the side of ATC.
It is NOT, the pilots made a mistake, more than likely influenced by to the pressure Ryanair puts their crew under.
Sorry, it seems according to Sylvia’s news clips, that “visibility was poor”.
How poor? Did ATC impose “low visibility procedures”?
If not, then I am sorry for the Ryanair captain who decided that he (or she) had enough room to pass behind and around the other aircraft.
Considering the nature of the incident, it would seem to me that the visibility had not really been too limiting.
Well, nobody was hurt, but I really feel for the girl who missed an important interview and as a result missed out on a career chance.
Rudy, I absolutely agree with you about that announcement. It is meant to imply that Dublin Ground somehow caused the accident which is clearly not the case.
It was a foggy day but there were no low vis procedures in place. I listened to the previous 30 minutes of ATC recordings and there were no reported issues. I should have phrased that better.
I had no problem with your wording but, as we both agree, with the way Ryanair were trying to put a “spin” on the account which was highly, and falsely, suggestive that Dublin ATC were somehow (partly) responsible.
A few people I know asked me about this incident and one or two wanted to know what the “winglets” are for.
So I opened your article which gives an explanation.
But this seems to be too technical for many who are not pilots. So I tried to explain in my own words:
We live in what is know at the “atmosphere”, a mixture of gases like nitrogen, oxygen, argon and some more. For us, oxygen is important because we need it for life.
We never think of it, but air has mass and thus weight. We all listen to weather forecasts and hear about “high” and “low” pressure. Ignore that; for this explanation it will be sufficient to know that in what is an internationally accepted “standard atmosphere”, at sea level we are carrying the weight of air, equivalent to a column of mercury 29.92 inches high.
Air being gaseous, this means that this weight translates in pressure acting in all directions.
An aircraft flies because the wings, cleverly shaped, are able to generate an upwards force at least equal to the total weight of the aircraft.
In order to generate this force, called “lift”, the aircraft must move through the air at a certain (minimum) speed.
At rest, on the airport, the force of 29.92 inches acts upwards as well as downwards and sideways.
What keeps the airplane firmly on “terra firma” is it’s weight. Depending on the type of aircraft and equipment, fuel, cargo or passengers and their luggage this can be in the order of hundreds of tons.
How can such weight go up in the air?
We are so used to it that we do not realise what force can be generated by air. Unless, of course, we encounter a severe storm and see roofs blown off buildings or trees falling.
In the case of aeroplanes, this force can be harnessed in order to create “lift”.
When an aircraft moves through the air, the shape of the wings separates the stream of air to flow over and under the wing.
Under the wing, the air will get thicker; this means more pressure.
The air streaming over the wings is being “stretched”, getting thinner which results in less pressure on top of the wings.
A bit like drinking lemonade through a straw: we suck the air out of the straw, the pressure in the straw gets less and the atmospheric pressure in the glass will push the fluid up into your mouth.
In the case of the aeroplane, of course, when it reaches a certain speed on the runway (which is also needed to allow for a “clean” airflow), the difference in pressure above and under the wings will overcome the weight of the aircraft so that it will be able to lift off and take to the skies.
Aircraft designers always have been looking for ways to make the aircraft more efficient.
We know that anything that moves through air (or water) has to overcome resistance, called “drag”.
Drag is a waste of energy. It requires fuel to overcome it. Although it is an inevitable by-product of the creation of lift, other forms of drag are a waste of energy (parasite drag) and therefore a waste of fuel.
When the aircraft moves through the air, the difference in pressure above and below the wings is considerable – a result of the “lift” that carries the whole in the air.
At the tips of the wings, inevitably, the high pressure air under the wing curls up and over the tip where is mixes with the low pressure above.
As the aircraft moves at high speed, this results in a long stream of rotating air extending far behind the aircraft. This is called a “vortex”and the rotation of this stretched-out “funnel” of air causes what is called “wake turbulence”.
This trail of turbulence can extend many miles behind and slightly below the airplane and, in the case of “jumbo” sized aircraft can even be dangerous to other traffic.
The “vortex” also causes drag, parasite drag. Lots of it.
For many years the aviation industry more or less ignored it because the solution is very expensive.
Learjet, a manufacturer of business jets, introduced a solution in the form or swept-up wing tips that formed a barrier against the worst of the vortex.
The Learjet 29, nicknamed the “Longhorn”, was a small aircraft and the “wake turbulence” did not really present a grave danger to other traffic. But it greatly reduced the fuel consumption.
Sometimes you can see the “vortex”. The air in the vortex is lower than the surrounding air. If there is a lot of moisture (water vapour) in the air, this will condensate in the vortex and we see what looks like “ribbons” or “streamers” trailing from the wing tips. What we see is in fact water.
As demands for greater fuel efficiency increased, both because of the need for increased range but also because of ever rising oil prices, now virtually every manufacturer of airliners is equipping their products with “barriers” to prevent or reduce the wing tip vortices – and therefore drag.
The most visually striking are the winglets. They are also, as recently proven, a bit vulnerable.