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Tuesday, May 29, 2012

SSJ100 Accident: Minister reveals the timeline

The Minister stated that the flight plan for the ill-fated second flight was an Instrument Flight Rule flight plan from Halim Airport, to the Pelabuhan Ratu area and back, with a planned altitude of 10,000ft. The flight was planned to take around 30 minutes.

0710UTC aircraft requested engine start.
0721UTC aircraft took off from Runway 06 and climbed to 10,000ft.
0724UTC aircraft contacted ATC at Soekarno Hatta airport along radial 200 from Halim VOR (VHF Omnidirectional Range beacon).
0726UTC aircraft requested to descend to 6,000ft.
0728UTC aicraft requested to make a right orbit over Atang Sanjaya (Bogor) Training Area.
0752UTC ATC attempted to call aircraft as it disappeared from radar.
0755UTC ATC reported the missing aircraft to the Air Traffic Service Coordinator.
0835UTC SAR "Uncertainty Phase" declared.
0905UTC ATC contacted Search and Rescue
0955UTC SAR "Alerting Phase" declared.
1122UTC "Distress Phase" declared after aircraft endurance time elapsed.

My flight path analysis/speculation of accident in Part 2 of article series
is very similar to the official statements made so far.

My Remarks
This corelates with my analysis at SSJ100 Accident: Innovent but Deadly Part 2Everything up to Point 3, matches. However, the descent from 10,000ft does NOT make sense if they planned to go to the Pelabuhan Ratu area, which is about another 25 nautical miles from where the aircraft did its orbit.

Based on this, a rough descent profile analysis can now be assembled, which will be put in Part 3 of the the "Innocent but Deadly" article series. (To be updated/linked here)

Why both hardcore A320 and B738 fans hate me!

I loathe Airbus versus Boeing debates. Yes, I hate it with a passion. In online forums, by the time you get to a dozen replies, the hardcore fans (ie: blind believers) start hijacking the topic with marketing gimmicks and junk and both sides try to drown out the facts (because it simply doesn't suit them).

One day, I decided, I had enough! I did a fuel burn comparison between the 737-800(w) and the A320-200 (Both CFM56-5Bs and IAE V2500-A5s). When I post them on 737 vs 320 debates, the comparison would either kill the discussion (because the fanatics have no room to wriggle), or it ends up being a slag-fest of outrageous claims.

Let's look at the comparisons:

Max Capacity Fuel Burn:

Simple, A320 wins on the trip burn, but 737-800 can get more seats in so the fuel burn per seat is lower in this aspect.

180 seat and 165 seat capacity or load fuel burn:

Once you go above 500NM, the IAE powered 320s, win. The CFM powered 320s, starts to win above 600NM.

100 seat load fuel burn

This shows that whilst the A320 would win over 600NM (again), its heavier airframe does penalize fuel burn for the shorter trips.

20-ton payload fuel burn

I did this because airlines do not solely look at cost per seat. Cargo, is an important source of revenue on passenger flights. So a Payload based fuel burn comparison gives an idea on how much profit one can make.

Notice that the IAE powered A320s, now start to win at a mere 300NM trips, whilst the CFM powered ones (again), need 600NM to start getting the edge on the 737-800W.

Time Comparison
Self explanatory

If I have an airline operations where my routes are predominantly 350NM or less, in terms of fuel burn alone, I'd be called a fool to start chosing the A320 with CFM56s. If my routes are predominantly over 500NM, again, I'd be called a fool if I choose the 737-800W.

But, we know that it is not that simple. After all, we still see 737-800Ws being churned out from Seattle, and the A320 with CFM engines are still selling well.

If fuel is cheap, by all means, go for the 737-800. If fuel is expensive, the A320 with IAEs do look attractive. The good news is, fuel price is an important factor, but is not the only important factor to consider. Maintenance cost is another major issue. The CFM56s are dirt cheap to maintain in comparison to the IAE V2500s albeit more reliable and durable, but the airframe maintenance costs are very similar between the A320 and the 738. This is also reportedly true for the price of the engines.

Of course, there are a myriad of other factors to consider too. At the end of the day, which one has the edge, could be determined by something as simple as who sneezed at the wrong time during the price negotiations!

Saturday, May 26, 2012

Batavia Air - In trouble? (Part 1)

A few days ago I tweeted that I heard 2 Batavia Air A320s having been repossessed by its lessor. It all started when I received a message early this week that several cabin crew and pilots have started saying privately that the airline was about to go bankrupt, with about 4 - 5 737s to be returned, and the 330s as well, and that the chief pilot had resigned.

No Cash?
I called up my sources, whilst they were chasing up the information, rumours, leads and leaks, I came across this article at TempoThe article dated 19 May revealed that 3 days beforehand a Batavia Air flight was delayed (by 5 hours after it was scheduled to depart, the flight, assumed to be from Pontianak to Jakarta). The passengers had decided to bring the airline's station manager to the airport security, and at the security office, a passenger stood up and addressed the other passengers.

"The problem here is that Batavia Air does not have the cash to compensate us in accordance to the regulations. In order for us to go home and rest, I am going to help Batavia Air."

Batavia Air at the airport had only IDR 16 million in cash, and the compensation that was due amounted to IDR 44 million. The passenger, Rasmidi, head of the Ketapang Regency Chamber of Commerce, then said, "I will cover the rest, please register yourselves to obtain the compensation. "I hope this serves as notice to Batavia Air, to reduce its flight schedules to match the small fleet that can operate."

It seemed that Batavia Air had overstretched its schedule.

Planes parked, or missing, and frequencies reduced: Signs?
As I wondered why on earth would Batavia Air not have cash for delay compensation, got to the airport the next day, and found both Batavia A330s parked together at the remote apron. This obviously raised alarm bells in my head, and prompted me to call up my sources again. By the evening, various sources began providing information. 

PK-YVF spotting at Singapore Changi devoid of titles
(Photo by: M. Aswin)
Another (ex-) Batavia A320 devoid of titles in Singapore Changi.
This one is suspected to be PK-YVH. (Photo by M. Aswin)
  • 2 Batavia A320s had been seen in Singapore, also parked together at the remote apron. Later I received pictures of the airplanes, both have had their logo and titles removed. The aircraft had been in Singapore since at least 16 May according to sources. One is identified to be PK-YVF and the other is suspected to be PK-YVH as the pair are reportedly leased from CIT.
  • 1 737-400, PK-YVQ is reported to have been returned to the lessor.
  • Both A330-200s are reportedly being prepared to be returned to lessor.
  • Another sources, had said that Batavia have reduced its flight frequencies on several routes by at least 1 flight a day.

Allegations, allegations and allegations - Is Batavia in trouble?
There have been numerous allegations of safety violations/breaches against Batavia. Most of the allegations in the past have been on the subject of crew flight hour limits being exceeded, whether weekly, monthly, or annual limits, are so many that I've lost count and stopped trying to remember them. The last time I heard of the allegation was if I remember correctly, when it was alleged that a DGCA inspector asked a Batavia pilot at Jakarta's airport waiting for his crew transport home, to show his flight log book, to which it was found that the crew had violated one of the periodic flight hour limitations. This reportedly led to immediate removal of the Operations Director.

Past allegations have also included questionable operational decisions, such as the company's route to Luwuk, where former crews claimed that they were not given charts of Luwuk Airport and that the procedures for route and the airport was made up as they go along. One or two allegations regarding operations of aircraft with no-go maintenance issues have also been made (one claim involved an A320 being dispatched on a single IRS, and another claimed that weight limits were exceeded).

Note: The above are allegations and cannot be independently verified.

Poor Maintenance cause delays. A delay (that is not caused by weather or factors beyond the control of the airline which does not include maintenance) exceeding 3 hours now require IDR 300,000 (about US$32) per passenger, cash compensation to be given to the passengers. If an a 737 has 10 flights a day, and each is delayed by over 3 hours, that's US$47,000 to US$55,000 in cash compensations. That amount is about the same as the monthly dry lease rate of an early 1990s built 737 classic. It takes no genius to figure out that delays caused by maintenance, is extremely expensive!

The overrun at Balikpapan in March was the second incident
involving the aircraft in the last few months.

The allegations mentioned above, are very hard to prove. We can believe in them or dismiss them as the claims aren't independently verifiable. However, the findings by the NTSC on the recent A320 runway overrun at Balikpapan ("Update: Batavia A320 Overrun at BPN 12Mar12" (dated 23rd April 2012)), does provide insight into the potential problems. The NTSC found that:

  • Batavia had not maintained the aircraft (involved in the incident) in accordance with the Airbus service bulletins, or even, Airbus's recommendation regarding rectification of the cause of the previous incident involving the aircraft. 
  • It was also revealed that the airline disregarded the Airbus recommendation for the problem on the brake servos be solved prior to its next revenue flight (after 1st incident at Jayapura) 
  • It was found that the airline's Technical Director was different from the Ops Spec submitted and approved by the DGCA.
The NTSC findings above are NOT allegations, they're not in the business of making allegations.

A330 Ops: Batavia's most descriptive bungle
Batavia made a bid in the 2012 Hajj tender. The airline had submitted its bid, which includes utilizing both of its A330-200s, and leasing 4 A330-300/A340-300 from Air Asia X, and 1 777-200 from EuroAtlantic, however Batavia also admitted they had not had any agreements regarding those leases because it was waiting for a decision from the Ministry of Religious Affairs before making commitments on the leases. The Ministry then announced that Batavia had not met the required qualifications specified in the tender documents, which included LOIs to show adequate commitment (ie: "not bluffing") on leases and also possession of IOSA certification. Batavia had none, and can only meet 7 of the 11 qualification criterias .

Batavia then lashed out claiming monopolistic malpractice as a reason for its failure to win a spot in the hajj flights. "This is not the first time we’ve proposed the service and not won," commercial director Sukirno Sukarna said to Jakarta Post, adding the airlines had tried in the past several years to win the haj transportation tender. But the Jakarta Post article showed that Batavia does not understand the tender: 
  • Last year Batavia had  its bid rejected because it did not have landing permits for the Hajj flights or had not applied for it, Batavia rejected such notion, claiming that it had the landing permits for Jeddah (except that it is for tourist and business (ie: regular scheduled) flights, and not Hajj flights which is a separate permit).
  • Instead of obtaining LOIs for aircraft leases, Batavia instead provided a loan commitment from a bank amounting to $1.3 million to lease aircraft for the hajj flights (something which is grossly inadequate, even for 1 aircraft!)
  • Instead of obtaining an IATA Operational Safety Audit (IOSA) certification, they said that "we have secured an ISO certificate that guarantees our service and safety. That is the same," according to Batavia's commercial director Sukirno Sukirna. DGCA spokesman Bambang Ervan had to explain to the media the difference between an ISO and an IOSA.
  • The ISO/IOSA games played by Batavia, isn't bought by anyone, because in March, Batavia actually said they were after the IOSA and that they were going to commence the process in 2013, and that Sukirno Sukirna stated that one of the reason is to be able to qualify for the Hajj flight tenders.
Outside of the Hajj bids, the A330-200 operations into Jeddah and Riyadh had seen poor load factors. Batavia initially announced it would fly to Haneda and has recently announced it would delay opening the route citing rising fuel costs as a reason (shouldn't they have factored in this?). If the A330-200s end up being returned to the lessor, I would not be surprised, in fact, such a move could actually save Batavia Air, but this doesn't answer the question as to why the 2 A320s are being returned.

So, who's pulling who's leg?
To conclude all the above briefly, I will add that around a year ago, a source from the financial industry mentioned to me that the airline's balance sheet was in a total mess, with negative cash flow all the time. He estimated that unless something changed, Batavia would run out of cash in about 11 months. The 11th month, was to be May 2012. If Batavia is indeed in trouble, would Rasmidi, who saved Batavia Air's station manager from being arrested or clobbered by Batavia passengers, get his money back?

Whatever is happening in there, hiccups do happen, and sometimes spectacularly when it comes to Indonesian airlines, but my hope remains: That the airline improve, turnaround, and come back as a strong and healthy player in our ever growing market. We don't want another Adam Air here!

Part 2 can be found HERE

Solo - Not a solo anymore

The writing was on the wall. When Air Asia (Both AK and QZ) announced that it would serve Semarang, I thought to myself, how long will it be before they stop flying to Solo?
Solo Adi Sumarmo Airport - New terminal, but Air Asia is leaving it behind.
(Photo by: Pizzaboy1 under Creative Commons)
Indonesia Air Asia stopped serving Solo ages ago, leaving only Malaysia Air Asia to serve this Central Java city from Kuala Lumpur. Then, Indonesia Air Asia started serving flights from neighbouring Jogjakarta, to Jakarta and Singapore, whilst Malaysia Air Asia started serving Kuala Lumpur.

After both the Indonesian and Malaysian Air Asia opened flights to Central Java Provincial capital Semarang, this month, Indonesia Air Asia opened flights Bali-Jogjakarta, and Malaysia Air Asia announced that it will stop serving Solo.

The tourism industry in Solo, was obviously not happy. From 02 September, Singapore's Silk Air will be the sole scheduled international air link for the city. The Solo Tourism Board has asked Air Asia to rethink it's decision, citing the massive investments it made in promotions will simply go up in smoke.

Let's look at the factors:

Air Asia's consideration:
Air Asia would not close a route if the numbers (passenger yields) were good. Solo's load factor (let alone passenger yields), fluctuate and the route isn't as profitable as the Jogjakarta routes.

Jogjakarta is a bigger market. The proximity of Jogjakarta from Solo, is always going to be a challenge for Solo Airport. Both cities are claimants to be the "center of Javanese culture." Historically, both cities were always at competition with each other, and each cities' royal houses, are bitter rivals (to the extent that the house of Jogjakarta was spun off from the Solo house after a bitter war in the 1800s).

The world famous Borobudur temple is just up the road from Jogjakarta, and the fastest way to get there from Solo is, via Jogjakarta.

The Jogjakarta Sultanate Palace, is a functioning palace. The Royal Family still use it, and still functions as a pseudo-seat of government for the Jogjakarta province (although the real business of modern day government is seated at other facilities). One can easily guess which palace is better kept and more attractive for tourists.

The other famous temple, Prambanan, is located between Solo and Jogjakarta.

Semarang's tourism market, is rising and is better located for attractions on the north coast, and has good land access to Jogjakarta.

So, tourism wise, which is a better market?

Business market:
Jogjakarta has a better business market than Solo. For the Central Java province, the business market is focused at Semarang, leaving Solo with mainly the tourist market.

The majority of the business activities in Central Java is distributed amongst the northern coast (which is served by Semarang), and the Semarang-Jogjakarta land corridor, whilst Jogjakarta also serve the business market of the southern coast of Central Java thanks to its location.

Future Prospects for Semarang and Jogjakarta
The current economic resilience of Indonesia means that airline business pax traffic is also picking up. This means better yields. Semarang and Jogjakarta are aiming to capture this. Semarang has planned a massive expansion of it's airport, where a new terminal on the north side of the runway will replace the currently tiny civilian terminal barely capable of handling more than 5 jets at a time. Jogjakarta's current airport is cramped, but expansion is being made to expand the apron and adding a taxiway to improve runway flow volume. But Jogjakarta isn't stopping there, they're planning a new airport which will be able to meet the demand growth.

Flights to Semarang and Jogjakarta, are more frequent than to Solo, making these two cities much more attractive than Solo. Jogjakarta boasts being the only Indonesia airport currently armed with a rail link, which serves both Jogjakarta AND Solo.

The odds are truly stacked against Solo.

Is there hope for Solo?
Yes, of course. But unless it acts correctly and quickly, it will be left behind.
Front Facade of Solo's new terminal built in the 1990s, opened in 2009
Solo's advantage is its new terminal, only a few years old. But, the city government needs to look at the airport as a business incentive tool, and not a cash cow. The local governmental stakeholders there, are Solo city government, and the Boyolali municipal government. The latter, has decided to slap a levy in addition to the passenger service charge.

Such a simple thing, but this leaves a sour taste to the passengers going through Solo Airport. This "additional levy" is collected separately. Semarang and Jogjakarta airports, don't have this.

As air traffic grows allover Indonesia, eventually, more airports will spring up, or airports in a neighbouring and competing city will improve. City and regional governments must begin to look at the airport as a tool, and not a cash cow.

On the market catchment area, it needs to look east. There are no civilian airports between Solo and Surabaya. This is an untapped market for air transport. The airport stakeholders need to start figuring out how to realize this potential, they just can't sit and wait. Right between Solo and Surabaya, is the city of Madiun, home of what was once Indonesia's largest aerodrome and now Indonesia's biggest military airbase. If we look at the experience of Malang (south of Surabaya), which is enjoying an economic boom after the airbase there opened up to civilian traffic, what's stopping the Air Force from deciding to open up Madiun to civilian traffic (although currently this is extremely unlikely)? When that happens, Solo Airport's market will only shrink further.

But if Solo and it's airport continue to think like THIS ARTICLE, they should save themselves trouble and quit now.

Friday, May 25, 2012

SSJ 100 Accident: Mythbusting the US Sabotage Theory

I didn't expect this to be bigtime news, but I guess since the rapid pace of development surrounding the Sukhoi Superjet 100 crash has slowed down, old rumors begin to surface. This time, the allegation of SABOTAGE.

Today, I read a tweet from Olga Kayukova (@Olga_Kayukova (Russian) / @Olga_Kayukova_e (English), Head of Communications, United Aircraft Corporation.

I'm amazed at how Olga can keep her cool over the past few weeks, with the amount of crazy speculation that has been raised.
  • "In our comments we rely only on the official investigation process. The media invents totally insane stories, another media repeats."
  • "Nobody in Sukhoi nor in UAC spreads or supports crazy ideas. It's speculations."

How did this sabotage rumor start?
It was reported by many witnesses, that on the day of the crash, a USAF C-17 arrived at Halim Airport, and parked on the South Apron (where the Russian Il-76s were parked during the salvage efforts). After the aircraft disappeared from ATC radar, the C-17 left departed.

USAF C-17 parked at Halim's Southern Apron
Photo also available at Jetphotos.
It certainly sounds fishy, and several journalists also asked me whilst interviewing about the circumstances around the accident. Since no one speculated further on the sabotage, I decided not to write about it, that is until I saw Olga's link to the Daily Mail article today.

"'We know that they have special technology - that we also have - to jam signals from the ground or cause parameter readings to malfunction,' said the unnamed intelligence official, highlighting a US military presence at Jakarta Airport from where the plane took off on May 9."

The facts as I know it - USAF Diplomatic Mission Support Operations
The US Air Force provides diplomatic mission support flights. 1 (a C-12 / King Air executive turboprop aircraft) is based in Halim in case Jakarta ends up in a riot that key diplomatic staff have to be evacuated. This aircraft runs around Halim airport regularly, but this was not what was reported during the day.

USAF C-12 stationed at Halim for Diplomatic Support Missions
Photo also available at Jetphotos.
The US Air Force aircraft present in Halim that day was reported as a C-17. How coincidental, SSJ-100 in Jakarta, at the same time the C-17 turned up. But, it's nothing more than a coincident. The USAF C-17 regularly fly to Halim Airport (once or twice a month, but no less than once every 3 months, depending on the agreement between the Indonesian and US Governments), also to support the US diplomatic mission in Jakarta. The aircraft would land, and park at the southern apron, offload stuff, and then onload some stuff, refuels, and depart again. Often, they spend about 1 - 2 hours before departure seemingly doing nothing.

What does these "support flights" do?
Simple: Emergency supplies for the embassy. The US Embassy, has emergency ration supplies in case of war or civil obedience. The amount of foods and supplies they keep, is not for me to know or disclose, but those supplies have to be rotated regularly, and the rotation require a closed-loop secure supply chain. That is why they had to use the USAF to support this supply rotation. 

Furthermore, the US does not want a repeat of the "Embassy Scandal" that happened in Iran, where shredded and destroyed documents were painstakingly reconstructed by the Iranians and then published as "Documents from the US Espionage Den" (اسناد لانه جاسوس امریكا), which contained information that are still classified by the US even today. One of the tasks was to evacuate shredded documents for secured destruction. I am told that when the aircraft has completed off loading supplies, re-loaded it, and then refuelled, one of the reasons for waiting around for an extra hour or two, was to wait for the last batches of "shredded documents" to be airlifted. And no, these documents are not carried in trucks, it can be as simple as someone with a small back pack, inconspicuously entering the aircraft, and leaving the aircraft without it.

I've seen several of these flights come in and out of Halim, especially back in the days when I flew in and out of Halim to the south coast.

They're just standard C-17s. No non-standard fancy gizmos put on them. The US is more scared of losing its secret technology in a plane crash caused by poor fuel quality being provided by civil suppliers (eg: Pertamina at Halim Airport). Observers of the military signals, intelligence, and counter-intelligence equipment in aviation know that to bring down an airplane such as the Superjet-100 in "mysterious circumstances", require lots of fancy gizmos, and at sizes that would make it obvious the aircraft carrying the gizmos are not a standard one!

My opinion remains, this USAF C-17 aircraft present at Halim that day, was a non-issue in this accident. Even a staunchly anti-American journalist interviewing me could accept that. I told him it would be far easier for anyone to bring the airplane down through other means (hey, ex-Soviet MANPADS are reported to be widely available in the blackmarket!) and getaway with it.

Thursday, May 24, 2012

SSJ Accident: Epilogue to one of the Departed

A farewell to the dead is always grave and sad but the words that we choose to express how we feel being left behind by those who departed often brings meaning to something that was previously under appreciated. This blog article is an epilogue given by my good friend  Himanda Amrullah, to Indonesia's leading aviation photo journalists, DN Yusuf, who perished in the Sukhoi Superjet 100 at Mount Salak earlier this month.

DN Yusuf immortalized in a wall poster in Manda's room

In 1995, I was still 11 years old. From a roadside magazine stall in South Jakarta, I got my very first Angkasa (Sky) magazine. After I got the magazine, I, who was still a young kid, was overjoyed seeing the photos of various aircraft type which gave me an everlasting impression, unlike those I saw in the Yellow Pages, which I used to look at before I got to know this Angkasa Magazine.

My parents supported my enthusiasm for the aviation world and would buy me an Angkasa magazine every month. It was from there where I began to know the names behind the photos that impressed me, along with the small letters in a corner of a photo, to credit the photographer, and the name that was stuck in my mind was, DN Yusuf, who took most of the aircraft and airport photos in Indonesia for Angkasa magazine.

When Manda heard about the tragedy, he waited at
Halim Airport to hear news, and took these photos.

Long before the internet invasion, long before the birth of Indoflyer aviation enthusiast community, or aviation photography sites such as airliners.net and jetphotos.net, it was the work of DN Yusuf that gave me the knowledge and opened my mind into airplanes and the aviation world. It was from his work that I began to know the detailed anatomy of various civil and military aircraft.

Between the accident site and Halim Airport, the
helicopters come and go...

It wasn't all about the images, the photos from DN Yusuf were accompanied by articles of Angkasa reporters. After I entered university, the works of DN Yusuf and Angkasa reporter Dody Aviantara, and the others in the Angkasa team, gave me the motivation I needed to chase my dream to become a pilot.

I visited the Angkasa office for the first time in 1997, but I did not meet DN Yusuf then. I finally met him in 2004, and it was then when I wrote my first article for Angkasa.

... and bodies begin to arrive...
After I got to know DN Yusuf, it was apparent to me that he was not just a photo-journalist doing his routine runs as a journalist for Angkasa. He had an aviator spirit and an overwhelming passion for aviation which he took along with him as he performed his duties as a professional photo-journalist. It was then obvious why his works were so powerful that it inspired many young aspiring youths wanting to jump into the aviation world in Indonesia.

Awaiting for the next one...

In 2008, I was given the opportunity to work as a photo-journalist with the Media Indonesia newspaper. Covering aviation news was something that I always looked forward to because it was then that I could meet DN Yusuf on many occassions. After covering the news, we would normally sit together and engage in a long discussion on aviation, and hear his experience covering various aviation events that came with challenges. Not long after those discussions, an article on DN Yusuf's experience, was printed on the Angkasa magazine.

The last time I met him, was at the Bali International Flight Academy graduation ceremony for the 4th batch in 2011, where the graduates all went to Garuda Indonesia. At that time, I was a pilot undergoing training with Lion Air.

DN Yusuf said to me:
"Bro, very few people have the opportunity to be like you, back then you were just a flight simmer playing at home, then you became a journalist and finally you're becoming a pilot.

Write about your experience, not many journalists end up as pilots, you have many photos and works that cannot be made by other people. I'll wait articles you write on your various experiences..."

Brother DN Yusuf, all this is because of the motivation and inspiration you have given through your work and perseverence as a highly dedicated photo-journalist.

The photo of DN Yusuf leads his own funeral procession

I thank you DN Yusuf, I am blessed and fortunate to have met a person such as you.

DN Yusuf and his colleague, Dody Aviantara, died while on duty covering the Sukhoi Superjet 100 demo flight, they died in honor.

Farewell My Friend...


I first knew Manda in his university days when life was always a dilemma between "what can be reached" and "what is dreamt." His story only spanned a few years but is filled with meaning, expressed in his "Children of the Sky" writings that, described his struggle to achieve his dream to become a pilot and the story of his best friend, the late Fandy Aditama, up to the point when Manda became a pilot with Lion Air. Upon reading his epilogue for DN Yusuf, I realized that I was not the only person who asked for Manda to write about his journey. DN Yusuf did so too. From dreamers to doers, the love of flight brings an abstract bond between enthusiasts.

Kill the drag!

A Taliban drag queen being escorted by Afghan forces to face justice!

No, the drag queen is just a joke, I'm talking about "winglets" and why is there such a variety?

In crew talk here, a winglet refer to two things.
1. That wingtip thingy-magic that's supposed to make our flights cheaper by saving fuel.
2. Male F/As that act like drag queens (ever seen one with his arms out to his sides and both hands pointing upwards when greeting you?).

It's no brainer, I'm not talking about killing male F/As that act like drag queens (even though I don't want to be locked up in a hotel room with one). I'm talking about our basic need to save fuel!

I'm not going to talk about the history of the aerospace engineers conjuring up funny equations. I'm also going to talk on the business side. The truth in the history of the winglet that we know today, is that no one cared about drag reduction wingtip devices until Iran decided to get people to think about fuel savings (if there's one pariah we need to thank with today's improved fuel efficiency technology, we reluctantly have to thank the Ayatollah).

Let's start with a little aerodynamics though. We don't put these things up just because they look pretty.

Where does the drag come from?
Lift for an aircraft is created because the lower side of the wing has higher pressure than the top. All sounds nice and dandy, but what about on the wingtip where both the upper and lower sides meet.

Tip Vortex by Citizenhom (Creative Commons)

Air is like a fluid, it always wants to move from high pressure to low pressure. So, the high pressure air near the wingtip, spills over to the lower pressure air, hence air from the lower side moves to the upper side of the wing, and as it moves forward, it creates a vortex behind it.

This creates drag... the vortex sucks its energy from the airplane, causing it to be less efficient.

Photo by NASA

As planes go higher and faster, this drag, increases. Scientists and businessmen in the industry agree to do one thing... 


Thanks to rising fuel prices since Iran fell, the urge to save fuel consumption continue. The old days of flying fast is long gone as it takes a lot of energy to punch an airplane through the air at high speed. Flying slower reduces the energy needed, hence lower fuel consumption. Unfortunately, lower speed means you've reduced the aircraft's total drag, but increasing the percentage of wing-tip vortex drag out of the total drag.

You can fight this drag by various means:
1. Increase the wing span whilst maintaining the aspect ratio. This reduces the lift-induced drag (including the wingtip vortices), but the question is, just how wide do you want the wingspan to be? There's a limit to this, both economic and structural constraints.
2. Optimize wing loading distribution by concentrating the lift nearer the body of the aircraft, so that you can afford minimum pressure differential at the wingtip, but this has manufacturing and maintenance complexities.
3. Put up a barrier!

Wingtip devices, are method number 3.

1. Containment method.
Ever seen a downward facing wingtip? This is made to contain the air from spilling over to the side. This is effective for slow speed aircraft, but for high-speed aircraft such as commercial jet, most of the spillover happens behind the wing, and the vortices are much much larger than the downward wingtip.

2. Wing-tip Fence like you find on the A300-600, A310-300, A32X family (except A320-100) and A380

Photo by: Joe Roland/V2 Photography
  • Method: Putting a small vertical fin at the wingtip, reduces the vortex effect. The small size focuses on the small radius high speed wingtip vortex which is the major component of wingtip vortex drag.
  • Benefits: Drag reduction at low weight penalty therefore still suitable for short flights. Small size does not affect crosswind landing/take off limits. Minimum interference drag too!
  • Problems: Not effective for speeds significantly higher than wing's optimum speed as the vortex size will render the fence useless. However, the Airbus use supercritical wings which makes its optimum speed on the higher end of the operating envelope.

3. The Standard Winglet like you find on the 747-400, A330 and 340

Photo by: Joe Roland/V2 Photography
  • Method: Adds aspect ratio without significantly adding the wingspan. Just add the span and hammer the tips upwards (sarcasm). The cant angle (angle of the wingtip going up) and the toe angle differs from aircraft to aircraft. The rotating vortex going up is stopped by the winglet, the cant angle will capture this to push the wing up, and the toe angle pushes the flow backwards as a form of, flow induced thrust. As long as the "induced thrust" is higher than the remaining induced drag, this method can be very effective.
  • Benefits: Big boost in aerodynamic efficiency and increases high altitude cruise stall margin. Enables the aircraft to fly higher.
  • Problems: Additional weight is something to watch out for. Interference drag exists (nothing stopping the lower airflow spilling over), and the boundary layer drag hitting a sharp angle will create another vortex.

4. Winglet-Fillet Combo of the MD-11

  • Method: Standard winglet added with a lower wingtip fence below the winglet.
  • Benefits: As per standard winglet but with lower interference drag.
  • Problems: I'm never clear on the penalties caused by this, but many suspect it was never really perfected as it's sole major user in the past, the MD-11, didn't really sell as well as we all expected (but that's another story).

5. Blended Winglet a la 737NG and soon the 320NEO

Photo by: Joe Roland/V2 Photography
  • Method: Same as the standard winglet but is not "stabbed into" the wing, instead, it is curved to eliminate the interference and boundary layer drag. This leaves literally no drag penalties for high speed cruise that dogged the standard winglet and winglet-fillet combo. And oh, yes, it looks good (to the certain extent that it tempted Airbus)
  • Benefits: Self-described in the method.
  • Problems: Weight is an obvious one, especially when deployed on "small" aircraft such as the 737NG. Crosswind limits are affected too, because you're basically adding two big sails on the end of the wings. The curve also require wingspan increases before you even go to the winglet. This eats gate space.

6. Raked Wingtips a la 767-400, 777-200LR/-300ER, 787-8

There's a pair of raked wingtip somewhere in this photo
(photo by: Joe Roland/V2 Photography)
Designers have long thought on how to reduce drag for more than the 3.5 % (wingtip fence and standard winglet), 3.75% (the winglet fillet combo) and 4.5% of the blended winglet. (Note. these numbers are just rough and I forgot where the numbers came from!) They broke the 5% barrier with the raked wingtips.
  • Method: Higher sweep angle at the wingtip than the rest of the wing.
  • Benefits: Increases aspect ratio & reduce lift induced drag, by spreading the wingtip longer with the higher sweep angle. This has the same effecft as the winglet and blended winglet without reducing the crosswind landing and take off limits. It is also surprisingly, not heavy!
  • Problems: Gobbles down gatespace like no other wingtip device because it really does increase the wingspan, this is why the 787-3 was designed with a winglet and not a raked wingtip.

But that's not all! Don't forget the other ideas:

7. Non-planar wingtip
This is a collection of various ideas. The A350XWB will use this by combining the blended winglet and raked wingtip idea. Another non-planar wingtip is the spiroid winglet. Aviation Partners (who designed the blended winglet for the 737NG) is researching this on some bizjets, and have reported reduction in fuel consumption by over 10%, however, it does look strange!

8. The MAX's hybrid wingtip

Lucky that looks don't always match aerodynamics
(image from Boeing)
How do you expand a wingtip fence, to become some form of a blended winglet without the weight, but also reduce the interference and boundary layer drag common to the winglet and winglet-fillet combo? Simple, you get a winglet-fillet combo, and hammer it to pieces till it's all bent with no sharp corners! The improved performance over the blended winglet, is around 1.5%, and you don't get the gate space growth associated with the raked wingtip. The only problem is, it looks ugly!

ENOUGH WITH AERODYNAMICS! What's in it for the passengers?
Let's start with what you don't want... 
  • Additional advertising space on the winglets (not available on raked wingtip). 
  • Lower costs. Let's admit it, fuel is just too damn expensive now, so reducing fuel burn by drag reduction, is making flights cheaper for us.

BUYER BEWARE! You may not get the results you expected!
I want to focus on the battle of the millenium, the A320 vs 737 war, which the upcoming battle is going to be the NEO and the MAX. I'm well aware of the touted benefits of the Blended Winglet. However the marketing material is so effective that we often forget the reality. We're now seeing 737NGs with those winglets flying short routes.

Here's the bad news from the realists. Short routes with winglets cost more than without! On short routes, climb becomes a greater portion of the total flying time, so does flight time spent at low levels, and it is in these conditions that the winglet's weight can end up as a penalty (climb), or its parasitic drag due to increased aircraft surface area (low level).

I looked at the trip performance numbers of the 737NG with and without winglet. Anything 300NM or less, you'd be stupid using the winglet. Above 600NM, the benefits start to come in. The Airbus A320 however, isn't a loser against the 737NG with the blended winglet, but the comparison between the two, does accentuate one thing: WEIGHT RULES AT SHORT DISTANCES! The A320's heavier airframe lose out on flights below 300NM, but beyond 600NM, it's all up to the aerodynamics and engines, and even with a mere wingtip fence and it's amazing supercritical wings, the 320 (with the IAE V2500-A5s or CFM56-5Bs) beats the 737NG on a per ton payload basis, consistently.

Before adding winglets to your 737NG or A320, consider
the composition of the mission profile
(photo by: Joe Roland/V2 Photography)
Airlines must therefore, when faced with the option to have wingtip devices, take a careful look. How long is their average mission profile? Are the rotation segregable or not between the ultra short-haul and the rest of the aircraft type operations? Does the added weight of the wingtip devices affect the landing weight limitations based on the mission profile to the extent of penalizing payload or not?

The questions to answer goes on and on as fuel prices go up and up.

However, operations department may be churning operating cost numbers behind the scenes, but the airline as a whole must not forget that the profit consists of two components: Revenue and Cost. Costs can be as low as possible, but revenue is also important. That is why, depending on the mission profile, getting a bigger and more aerodynamically efficient wingtip device for your aircraft, may not always be the answer. Operations department must be more commercially aware.

But why am I talking about this when the new aircraft with options to have a wingtip device or not is only the 737NG? Simple, the A320 and its upcoming NEO will have the option of a wingtip fence or a "Sharklet"...

(image from Airbus)