Last 11 June, PH-NXA was the first to put its wheels on the ground at the eastern airport at 09:50, followed that same day by PH-NXD at 14:55. On 24 September last, PH-NXE arrived at 11:03 a.m. as the third of KLM Cityhopper's fleet and on 15 November last at 09:55 a.m. came number four, PH-NXB. ‘Maybe two more will arrive, maybe three more, but it could also be that NXB is the last,’ says Jeroen van Eijk, project manager at KLM Cityhopper.
Global problem
Pratt & Whitney (P&W), the US manufacturer of the Geared Turbo Fan (GTF) engines, is struggling with an adjustment on the engine maintenance schedule that affects all platforms operating with these engines. Gertjan Lichtenveldt, Fleet Manager at KLM Cityhopper, points out the consequence: ‘P&W has a problem with engine availability worldwide as a result, not only on the Embraer E-Jet E2 family, but also on both the Airbus A220 and the Airbus A320neo family. On the former two, you don't have engine choice, on the latter you do. With KLM and Transavia it does not play a role, their neos are equipped with engines from General Electric (CFM International LEAP <Leading Edge Aviation Propulsion>; LK). But IndiGo has them, so does Spirit and so does Wizz Air.'
India's Go First even claimed that their bankruptcy was due to the poorly performing engines on their A320 fleet. Still, there is a bright spot. Gertjan: ‘The engines now coming out of the factory at P&W are good. The problem is with 18 of our 22 E2s. In the three that will be delivered next year, it is not an issue.'
A whole scenario
The engines of the troubled aircraft all have to go back to the engine shop. ‘We have a contract with P&W for that,’ Gertjan says. 'Apart from America, there is now also a branch in Poland. Our engines go there by truck. The problem is that we lose them for so long. Clearly, we are not the only ones: around 3,300 engines need to be inspected on seven parts worldwide. Normally an engine is checked periodically, now it depends on when it was delivered, in what condition and what stage it is in. Some need to be checked after 4,000 hours, some after 5,000 hours. It is a whole scenario that can take 90 to 240 days. Of course, the fact that motors come off a machine does happen frequently, which is why we have four spare motors as standard. But those four are not enough to solve this problem.'
A choice
‘Once the motors are off a machine, that machine is off,’ Jeroen continues. 'You don't do anything with it anymore and that's not good for an aircraft. Normally, you do an engine swap and the aircraft can go back into operations with a few days. When it became clear that the engines of our eighteen E2s had to go to the shop, we knew we would go through the spare stock at some point. That meant a choice: either we have crates without engines at Schiphol for a long time or we pull them out of the operation. Leaving them at Schiphol is at the expense of these beautiful new machines. In addition, they continue to need attention because you have to meet certain maintenance requirements, while we want to focus primarily on flying. So we decided to house some of our E2s elsewhere and keep the remaining fleet out of harm's way.' Gertjan adds: ‘The engines taken out from under these aircraft will also act as spare engines for the rest of our E2 fleet for the time being after P&W's inspection.’
A perfect spot
Once the choice was made, the question of where KLM Cityhopper could house a number of E2s on a long-term basis could not fail to arise. Gertjan: ‘America was out of the question anyway. Unlike our wide bodies which are on intercontinental routes, our narrow bodies don't have all the equipment to fly there. In Teruel, we have experience as a storage and dismantling site for our 747s, but Airbus also has maintenance hangars there and it was full. Then I thought of Woensdrecht where we were once with Fokker. But that too was full. Then thoughts turned to Groningen, Twente and Germany's Weeze. The latter option was also already full. We knew Groningen because our 737s were there during corona. In the end, we went for Twente, a perfect spot in a secluded area with excellent facilities. Moreover, not too far away. The machines we took there we ultimately want to fly again as soon as possible.'
Sufficient space
Twente Airport is part of Technology Base. The location not only offers opportunities for flight operations, but also for testing and training. Several companies are based there, including AELS, NLR and TKH Airport Solutions. When aircraft were grounded worldwide during the corona crisis, demand for parking facilities also arose at Twente Airport. ‘At the time, aircraft stands, vops, were constructed, mainly to be able to put down wide bodies,’ says Gerben Groothuis, Business Development Director of the airport.
'That was somewhat opportunistic because after corona there was no acute demand for it. We did have discussions with aircraft leasing companies who might want aircraft parked for a while at the end of the lease period. In 2021, there were five Embraer 175s from Danish leasing company Nordic Aviation Capital here. At the time KLM Cityhopper came asking about their E2s, it was empty. But even if those 175s had still been there, there would have been enough space. In principle, we can accommodate about fifteen to twenty narrow bodies without compromising our own operation. It depends a bit on how you put it together. And, of course, it also depends on the size of the aircraft. I am currently in talks with a couple of parties who also have E2s. If those machines would have to be added now, it will work. And if they don't come then that doesn't mean the end of the world either. Everyone solves it in their own way.' Even from AELS, there is still sometimes interest in putting down aircraft on the vops while waiting for their decommissioning.
One outcome
That the climate in the Netherlands is not exactly favourable for putting down aircraft for long periods of time can be seen in an Airbus A220 that has been stored at Twente Airport for some time. Meanwhile, the plane has turned slightly green in several places. ‘Once we had decided to park some of our E2s at Twente for a longer period of time, I remembered that I once saw a machine packed at Fokker in Woensdrecht,’ says Gertjan. 'That seemed like a solution with the added advantage that in that case you don't have to run certain systems anymore. I remembered that Cocoon handled packaging for Fokker. So I suggested googling that company. To our surprise, it even turned out to be in the Netherlands, pretty much next door to us, in Hoofddorp.'
Fungi
It was not only for the packing work of the E2s that something had to be arranged, but also for removing the engines and preparing the crates for long-term storage in accordance with Embraer's instructions. ‘Normally we do such work ourselves in consultation with the engine manufacturer and other parties,’ says Gertjan. 'But now, as Jeroen pointed out, we very deliberately wanted to decouple it from the operation. For that, we successfully knocked on Samco's door. This aircraft maintenance company re-engages as soon as a machine is ready to go back into operations. As long as the E2s are packed, a fuel sample will have to be taken every seven days for the time being to check for any fungi (paraffin fungus; LK) developing in the fuel tanks. So far, nothing has been found so we will have to discuss with Embraer whether to continue with that.'
Biscuit factory
‘It was quite exciting when our first E2 was about to leave for Twente,’ says Jeroen. 'This is an airfield that is not part of our destinations. It requires a flight plan with VFR and the turning point to be made on approach also poses a separate challenge. But thanks to all the joint preparations with Cocoon, Samco and the Twente airport, what was so exciting at first gradually turned out to be like a biscuit factory where it is known how to bake biscuits. Having a plane packed for two, three months, you don't. From the beginning, we said that this project will take about two, maybe even two-and-a-half, three years. The bandwidth is very much dependent on performance of P&W's engine shop.'
Excluded
‘Packing an aircraft takes us six weeks,’ says Alexander van der Zee, owner of Cocoon Holland B.V. ‘When Fokker still existed, we packed many unsold F27s that the aircraft manufacturer had produced ahead of time. The moment they were sold, we unpacked them again in two days and they could be prepared for the customer. We also packed types that were developed later, as long as the company kept the production lines full.' Cocoon packs much more than aircraft. Consider naval vessels, components of LNG carriers and expensive equipment such as heat exchangers and inverter installations.
‘From World War I, people learned that just putting stuff anywhere results in you never being able to use it again,’ Alexander explains. 'Towards the end of World War II, the Americans therefore developed the Cocoon Mothballing System, a system that allows precious equipment to be mothballed, so to speak. This system creates a hermetically sealed plastic cocoon around the equipment. Inside that plastic skin is a conditioned climate that controls humidity and keeps it stable at around 38%. Rust, mould and dehydration of rubbers and plastics are thus eliminated. There is ozone in everything. The system also removes ozone from the air.'
Like a spider
At Cocoon Holland B.V., they do take a very different approach to packing than Christo and his wife Jeanne-Claude did at the time with the Reichstag and the Arc de Triomphe, among others. Not that the company has never been involved in the realisation of an art project: in 2009, OMA's Prada Transformer, a creation by Rem Koolhaas, came to fruition with the help of Cocoon. But: ‘When it comes to cocoon mothballing, there must be space between the cocoon film and the object being wrapped with it,’ Alexander explains.
'Using tubes and hoses, we create that distance. We produce the cocoon film ourselves. Cocoon is a sprayable PVC whose properties are that it is airtight, elastic and tough, as well as having high weather resistance. Once the first layer of cocoon film is applied, we reinforce the seams using a webbing technique. We then apply several layers of cocoon film and connect the air circulation system. Just like a spider spins its own threads, we seal all the holes with our spray gun. Per plane, the undercarriage is put in an aluminium container because you have to connect somewhere airtight. Besides, you don't want moisture from the concrete base to get into the plane. Both the deflated tyres and the aluminium bin are packed. This makes them part of the Cocoon Mothballing System.'
Time machine, time capsules and Mr Stanley
‘We do joke about our E2s being cocooned,’ says Gertjan. 'With this approach, we are the first to come up with a time machine. We can stop time, maintenance time, which after all is stopped for these E2s that are now in a cocoon.' Jeroen looks ahead in time, also with a joke: ‘Once we have enough engines to bring them back Mr Stanley comes along. The idea is that when we open it up the cabin will just still be as it was and the livery will still look neat.'
Gertjan interrupts him: ‘These E2s are also a kind of time capsules, where it remains to be seen how everything they are fitted with is preserved. In fact, nothing has been taken out or taken off except the engines, APU and batteries.' Once it gets to the point where it is the end of the line for the cocoons, a whole maintenance package will obviously have to go over the machines. ‘But anyway, so that's just for the next step,’ Jeroen states. 'Once they are retrieved, we apply the principle of first in, last out. So the machine that went to Twente first will be the last to leave. This is also how they are parked; the first to arrive wouldn't even be able to get past the others without a lot of fuss.'
With thanks to Up in the Sky, Remco de Wit and Tim Volmer for the photo..
