As a furloughed airline pilot I can speak from experience. The one thing that CNN has omitted is the actual reason the aircraft were prohibitted from departing. What regulation or law were they violating? Safety as far as departure path? Safety as far as noise abatement procedures? Safety as far as climb gradient? Performance? Was it really "safety" as generally defined, even by those of us in aviation, or was it more of an "envirornment/carbon" thing?
The reader will have to look this up on their own, which most people won't do. In the end, most people will go away from this story thinking that Lufthansa screwed up. Seems CNN told the truth in saying the planes coudn't leave but didn't report on the reasoning, therefore leaving a piece of truth out of the story. When I was a cadet and then in the military this was known as quibbling, if I remember correctly. Regardless of who does it, it's not nice.
According to the story, the folks at Lufthansa actually had permission to do the operation, to include taking off again. Unless Lufthansa is lying, that is. In the government's defense, it wouldn't be the first time an airline messes up. Then again, it may have been some idiot on both ends that just didn't send an e-mail or make a call, or maybe something wasn't followed up on.
I'm not sure about Europe, but here in the U.S. you have operations like this under what is known as Part 91 of Title 14 of the Code of Federal Regulations (Part 91; 14 CFR) which is basically the operations of aircraft not involved in compensation (i.e. no pax or cargo, just ops). It covers other stuff as well (maintenance flights, repo flights, etc.) and can be used for compensation under certain cercumstances, but it's not the norm. Usually "income" flights are done under Part 121 (scheduled airline), Part 125 (same, but unscheduled for the most part), or Part 135 (scheduled and unscheduled charters, etc.). I'm guessing Europe must have something similar, which means there should be no reason for something like this to happen on such a grand scale. One or two planes on different days, maybe. This many planes?
In the end, if Lufthansa is correct and they were told they could do the "in and out" flight, then the government made the "oops" in this one. If Lufthansa is lying, then they're the ones looking at the blame. Either way, if there's any gray area at all on any operation, we as Pilots in Command (PIC) are the ones that have the final word on whether or not the airplane gets airborne to begin with. Frankly if I wasn't certain 100% sure everything was good to go, we didn't puch back - much less take off and land. I can think of a few times dispatch really hated my guts.
Considering the lack of details, it looks like we'd have to do a lot of searching just to figure what was violated. Regardless of who messed up, it seems the only winners here were the local Dutch government since Lufthansa had to pay fees for having their aircraft on the ground. Since that's based on what the aircraft is certified to carry, I'm sure the local folks were in no rush to, "fix the glitch," like they said in the movie "Office Space."
At least nobody was hurt in any way, which is always the most important thing when any one of us messes up!
Post by Pixel Pilot on Nov 5, 2020 10:56:51 GMT -5
Thank you Jorge for your response. I always appreciate it when a "real pilot" joins a conversation and gives us the benefit of their experience. Below I'm quoting from the article what I believe is some pertinent information.
From CNN "Prior to this resolution, the ILT told CNN Travel that the planes couldn't depart because Twente Airport didn't have the right safety certificate." "The airport's infrastructure is momentarily not suitable for the takeoff of larger and heavier aircrafts," an ILT spokesperson told CNN Travel last Wednesday. "Nor has the aerodrome operator requested for permission to deviate from the international safety rules. This can pose security risks."
"Lufthansa told CNN Travel that when the airline landed the six Boeing 747s back in the summer, larger jets were permitted to take off for non-commercial and storage reasons."
"ILT = Netherland's Human Environment and Transport Inspectorate"
I hope this helps to clarify what the problem was.
Caution - nerd alarm. And yes, I spent way too much time on this, but it was interesting to learn new things.
Nowadays I live just 20km (12.5mi) as the crow flies from this airfield, making me dig a little deeper into the matter when it made the news. To my surprise, this local fray made it all the way to main stream media around the world. When it even appeared here I decided to find out all that I could about it.
As reported, the dispute was resolved though co-ordination relatively quickly and the first 747 left shorty thereafter. Two more should follow this year, the rest in 2021. As CNN and others mention, the dispute evolved around the airport's Safety Certificate (Veiligheidscertificaat), issued by ILT. This is required by national law to operate an airport, as is the Airport Ruling (Luchthavenbesluit). ILT insists Twente's certificate never did allow for 'planes of this size and weight' to depart and has always been limited to just their arrival. They also emphasize they had not been informed of the intended arrival of these specific planes - which is not surprising considering all other factors. Apart from that, the six arrivals were well-covered by national media and spread out over nearly two months.
The airport is, or was, convinced their permission involved both arrivals and departures, even for heavies, for the specific purposes of storage and maintenance. They claimed ILT had been changing the rules on the way and were ready to go to court to have that undone. It was also known, from the arrival of the first two, that they were not marked for dismantling on the field. Based on their view, the aiport undoubtedly told LH the planes could leave again if required. Interestingly, published procedures for EHTW still indicate so!
The (commercial) operator of the airfield is the one receiving the parking fees and it was also the party trying all it could to have LH fly them out of there, so that was customer-friendly. Their higher objective though is to one day obtain a permanent license for wide body operations in and out, in order to operate EHTW as a maintenance base for heavies.
From my own experience (including direct personal interaction with ILT several times, during my ten years as the chief instructor TWR at EHAM ATC) in matters like this, usually just two or three people on either side are involved to sort out matters. This makes the whole process rather vulnerable to mistakes and I have known both sides to be wrong. Agreements were always reached in the end, let that be said. But this principle of decisions with broad impact depending on the specific knowledge of a few is much more widespread than most people are aware of - not just in aviation.
Twente Airport is a former Royal Netherlands Air Force base, that had a secondary role as a regional airport for passenger flights until early this century. It lost its military status in 2005 when the last fighter squadron left, effectively closing it down altogether. In 2017, it was reopened for general aviation only, on a PPR24H status (prior permission required 24 hours in advance), with limited opening times and no instrument procedures. Within this tight frame, it was agreed that airliners of all sizes would be allowed to arrive here, to be taken apart by specialised companies. Large parts of the field have been closed like most taxiways, the shelter areas, the small civil terminal and the crosswind runway. What remains in use still has the physical characteristics of a standard NATO base of the 1990s. Including this is the 2400 x 45m (7875 x 147ft) runway (to be exact: 2406m operational length; the "3-kilometre long runway" the airport claims on its website includes the stopways). It is certainly not the 'tiny airport' CNN says it is, it just has a 'tiny status' nowadays.
The Safety Certificate is, so I learned, among other things based on rules for aerodrome design as laid down by EASA (the European Union Aviation Safety Agency) that have in turn been based on ICAO Annexes. According to these rules, EHTW is not suitabe for operations with virtually any wide body aircraft because the runway has no shoulders. The outer main gear wheel span (OMGWS - yes that is a concept) for the concerned airplane categories dictates runway shoulders for a total width of 60m (197ft). ILT indeed mentioned the lack of shoulders as one of the prohibiting factors.
Nevertheless, everyone agrees EHTW's Safety Certificate does allow for wide body arrivals, so an exemption has obviously been granted by ILT in that respect. This is also in line with the governmental Airport Ruling. Unfortunately, I have not been able to find the certificate itself online, so we can only guess as to what wording on this specific subject has been interprated differently by either side.
In the eAIP (electronic Aeronautical Information Publication) the official data for operators is published, under Aerodromes - EHTW Enschede/Twente. The Aerodrome Chart shows that most of the remaining taxiways and aprons have been restricted to towing only. The textual data gives the strength of those and the runway classified as being at least 62/F/A/W/T. I had to look that up as well but it means even a fully loaded 747 can roll anywhere safely here, within the other restrictions of course.
The textual data also mentions, under AD 2.9, that the C-apron is available to aircraft of categories A, B and C. I am not sure which type of category applies here, that based on circuit speed or the one mentioned above, but 747s are of a higher category in either case. Interestingly, three of the six LH 747s had been parked on that C-apron, including the one that has left meanwhile. Twente had been pouring concrete recently to build extra stands there, especially to accomodate the LH 747s. The discrepancy with the AIP could stem from the difference between taxiing and being towed.
With the 'size' factor clarified as much as I can, that still leaves the 'weight' factor mentioned by ILT. In relation, they stated EHTW had been working on upgrading its certificate, but has not yet succeeded. I can only guess here but I suppose this specific part of the problem might concern the airport's Safety Management System, another demand to obtain the certificate. Perhaps ILT has found the fire & rescue protocols to be inadequate? Again, looking at the AIP that seems strange, but I cannot think of other reasons. The AIP states for EHTW under Aerodrome category for fire fighting (2.6): "Required CAT O/R 24 HR PN" meaning the required category will be available, given an advanced notice of 24 hours. Under Remarks here it say "NIL", so that certainly suggests no restrictions.
Finally, flight procedures. ILT stated 'the departure procedures for these types of aircraft have not been granted approval yet'. Again, this contradicts with what is published in the AIP.
The European version of Title 14 of the Code of Federal Regulations, as mentioned by Jorge, is the EASA Air Ops Regulation, I think. This is another subject I learned about while digging into the matter. Information is published on the EASA website. Most commercial operations, ranging from a small cargo charter outfit to a major passsenger carrier, fall under Part CAT - Commercial Air Transport, it seems. Under these rules and perhaps a lack of exemptions in this country, it is hard to keep a DC-3 flying in the Netherlands by the way. The club owning one had to obtain an Air Operator Certificate, the same as a major airline, in order to be allowed to sell tickets for pleasure flights. This revenue is needed to keep the bird in the air. DDA Classic Airlines managed to do so, but it has not been easy and has made them a sort of outsider in European classic aviation. Their AOC prohibits them form participating in many enthusiast events.
Back to the AIP for EHTW, it says near the top under Remarks (AD 2.2 - 8): "When an aircraft of ICAO approach category D operates to or from Twente Airport, the flight crew must have read the local briefing and completed the mandatory test prior to the flight(s)". This is the first item there, certainly suggesting that Cat D aircraft are permitted to depart.
Under AD 2.21 it says for noise abatement, intersection departures are not allowed for turbine aircraft. Apart from the deficient underlying theory that full-runway departures will always produce less noise for the environment, this is a bit of nitpicking really. Rwy 05 has no taxiway to its very beginning, the first one is at some 100m (300ft) down the useable runway. As a 747 cannot make a 180 on this runway, it has to be push-pulled into position if departing from 05. A nuisance, but not a problem, and to reach rwy 23 they have to be towed as well, anyway. Further down under AD 2.22 we read: "Two circuit areas have been established at Twente Airport. [...] Circuit area south of the runway is intended for aircraft types of ICAO aircraft approach category B and C, or aircraft operated in accordance with EASA Part CAT or NCC". This is followed by more information on how to use circuit area south and detailed descriptions of the Visual departure procedures, again including "aircraft operated in accordance with EASA Part CAT". Obviously, Part CAT is where the LH 747s fall into.
All in all, nothing in the AIP suggests the six Jumbos could not depart EHTW legally (and this information is still in the publication cycle that will be effective as of 3 December 2020, for at least the following four weeks). ILT is probably right on the restricted nature of permissions and exemptions granted through the Safety Certificate. After all, they are the ones who issue it. Another indication is the airport agreeing to a one-time exemption for the departure of the six heavies, implicitly acknowledging the underlying restrictions. In that light, I find it misleading that a full set of procedures is still published officially. One could argue that potentially forbidden operations will be prevented by crews having to go through the mentioned briefing and test, but what is the point of publishing procedures that may not be used? AFAIK, AIP content for aerodromes is delivered by their operators and overseen by ILT - exactly the two parties involved here! Even if there is the aim of eventually enabling these operations, why not just hold off on publication until that is a fact, like in all other cases? A lot of nuisance could have been avoided and energy saved, if you ask me.
Post by Tom/CalClassic on Nov 17, 2020 10:18:32 GMT -5
Probably (as we say in the US) “the left hand didn’t know what the right hand was doing”. Part of ILT and the airport are thinking it’s OK, while the rest of the ILT is thinking it’s restricted. Not unusual for large bureaucracies, and probably unavoidable (but let’s try to minimize it). Hopefully LH will not take the airport’s word next time and get a ruling from the ILT in advance (although I have seen such organizations reverse themselves afterwards so there is no way to be absolutely sure).
Erik - Thanks for the explanation of what's going on, and I echo Tom that this sounds like a left/right hand issue.
Also, about the "no intersection takeoffs" thing - Noise Abatement is not about reducing the noise amounts in general. It's about limiting the noise *level* outside the airport perimeter. As such, an intersection departure would place the aircraft at a lower altitude when crossing the airport boundary, necessarily increasing the noise level outside the perimeter. As such, to comply with noise level requirements, departures are limited to full-length operations to ensure the aircraft cross the airport boundary above the minimum altitude required to attain the permissible noise levels.
As annoying as Noise Abatement procedures can be, I spent some time while in Denver researching and learning about the noise abatement procedures and monitoring that was done for Denver International Airport during the transition from basically unrestricted noise levels to Stage III compliance. They spent several months having airplanes fly various proposed procedures (both vertical and horizontal paths) and included intersection departures for certain smaller jets. The difference in noise levels outside the perimeter fence from just having a plane take off 1000 feet (300 meters) down from the start of the runway was almost a 10db difference on several types. That's massive. By simply ensuring full-length departures for aircraft that were not Stage III compliant and giving them a different horizontal routing, the noise levels over the (now) residential developments south of the airport were reduced by over half. Today, I'm pretty sure those noise levels are even lower with most aircraft now complying with Stage IV noise requirements natively and those that don't being full Stage III compliant.
Also, Denver International is one of the few US airports that I know of that maintains a comprehensive online web page of all their noise compliance and management. Others you can get by request, but DIA puts it right out in public - www.flydenver.com/about/administration/noise_management
Last Edit: Nov 17, 2020 11:23:11 GMT -5 by capflyer
Thank you all for reading through my lengthy post - and there is nothing wrong with nerdy, haha. I too think the left/right hand scenario is very plausible here.
Capflyer, I appreciate the info about Denver, those are impressive results indeed. At Schiphol as well, noise management is always present in the operation and adds a great deal of complexity to it. There, too, comprehensive information is available online. Clarification of the basics from the Dutch ATC organisation LVNL in Dutch and English, like here on its website and a heap of information in Dutch on the community website here. All propeller aircraft are exempted from these noise rules by the way, which used to be funny say 20 years ago, when comparing an An-12 departure to that of Cessna Citation.
The leading criterium for Schiphol is the cumulative noise load on homes in the vicinity. Nowadays, turboprops as well as jet airliners initially climb like homesick angels, as long as they are not A340-300s or fully loaded cargo 747/MD-11s. Because of that, Schiphol switched from prescribing NADP (Noise Abatement Departure Procedure) 1 to NADP 2 several years ago. NADP 1 is best for noise abatement directy after take-off while NADP 2 is best for noise abatement a bit further on in the climb. From practice I would say between one and five minutes after departure, to roughly 10-15NM from the runway. With today's huge initial climb rates, there is little to be gained very close to the field, hence the change. And here comes the one thing that has been left out of the equation so far: derated take-off.
I do not have any numbers to go with this, but at Schiphol it was found that with derated take-offs, many departures produce a larger 'noise footprint' than with standard take-off power, as they fly lower along the initial track. I think this was the case with both NADP 1 and 2. As derating reduces engine wear and therefore improves economics and to an extent even safety, offering more runway for departure will result in more derated take-offs.* This is what I meant before by 'the deficient underlying theory': at least where I worked, there is actually nothing conclusive to say about the effect of intersection departures on the overall noise burden around the airport. One cannot tell in advance which flights will apply how much derating from which departure point, and what the overall effect on noise from that will be. At night, full-length departures are still mandatory at Schiphol for noise reasons, which makes sense for the nocturnal cargo flights but less so for the rest. During the day, intersection use is based on a combination of operational factors.
* We used to tease pilots with this, during quiet times at the satellite tower for the remote runway. We would grant the use of a popular intersection and then ask Schiphol-based pilots "Doesn't the company prefer you to apply maximum derating?". After a bit of silence the answer then often was "We'll take the beginning...".
Edit P.S.: It just occurs to me why derating might not/hardly play a role at Denver: that airport has an elevation of 5433ft MSL, with a density altitude even higher in Summer I suppose. Schiphol is at minus 11ft, a totally different situation.
Thanks for the response. Even with the altitude, while using a fixed de-rate is probably rare except when flying extremely light or ferrying an aircraft, using flex thrust is the norm in the US for pretty much all carriers regardless of airport. This provides the best balance between all factors. Using an intersection simply affects the flex temp used, which might bump initial thrust some, but you'd be surprised how much power that pulls off, even at somewhere like Denver. Then again, NADP in the US is more of a company selection but much of it is a non-issue with the new RNAV DP's coming into widespread use that ensure the initial climb phases reach a height where no matter what noise abatement or thrust setting is used, the noise impact will be minimized. It's seemed to be pretty effective (especially if you look at the DEN website) since almost all of the complaints are coming from people who are either complaining to complain or are complaining about the wrong airport (several of those on the list I suspect were about airplanes leaving either Jeffco/Rocky Mountain Regional, or the military jets operating out of Buckley AFB).
Post by mrcapitalism on Nov 18, 2020 14:18:48 GMT -5
It would be interesting to have a discussion on the differences in takeoff profile for propliners vs jetliners (acceleration below 200ft vs acceleration at 1,000ft), and when that was implemented and why (safety? purely noise?). Have jetliners (like the B707) always flown a minimum airspeed climb to accelerate at altitude, or did they at some point accelerate above the runway like a DC-6?
When doing some research on EHAM, we also realized that certain runways are not available for takeoff, and others unavailable for landing. Since terrain or airspace isn't an obvious concern I suspect the answer was noise. They are committed to the point of not publishing TODA, ASDA, or LDA in those cases.
On my smaller turbine aircraft flex is the standard, but there is a limit to the amount of de-rate available. It seems at some point the thrust is reduced to the point where further reductions don't yield any benefit. Since even max de-rate (flex) performance will usually exceed departure requirements, the prohibition on intersections would probably have a larger impact than the choice of flex in my case.
Also might be useful to consider that while a de-rated aircraft would be flying a shallower climb profile, it's engines would be at a reduced thrust setting, possibly providing an offset.
CAPflyer, using the RNAV DP's to ensure noise regulations are met is interesting. I wonder if that will come our way as well. At Schiphol, the aim still is to minimise the total noise load on homes from the perimeter to quite far from the airport. 2020 was to be the year where new runway use rules could be established, but then COVID decimated traffic of course and now the cards will have to be dealt anew. Who knows what we may get.
MrCapitalism, indeed 18R/36L may only be used from/to the north, and 18L/36R only to/from the south for noise abatement reasons (except in emergency). 18L was closed as a landing runway in the late '80s but 36R incidentally used for departures of Fokker aircraft right out of the factory until some time in the '90s. Such a shame we lost that. The 'Polderbaan' 18R/36L was built just for its present use.
Interesting question on the climb profiles! Makes me think of the Russian habit of just flying aircraft off the ground, as opposed to rotating to be airborne. They did that with everything that has now been banned in our parts, for noise or safety (alas!). Funnily, with the Russian AirBridgeCargo, some of that seemed to have crept into the way they operate their 747s. They always come in very fast, like 170kts over the threshold as given by radar data, and then of course rather 'flat' which reminded me of departing An-12s and Il-76s just rolling until the wheels lost ground contact...