I have been thinking what are the advantages and disadvantages of push-pull configuration. Everyone knows that push-pull has both disadvantages of pusher and tractor configuration but also implements a simple to control center line thrust operation for a critical single engine situation. However, there is more than that to it.

If you think one-of-a-kind aircraft, e.g. what Burt Rutan used to do during the early years. You want to build a twin on a shoestring budget. Then you realize that you have to buy two of everything. What if you have two engines already hanging around but they are not exactly the same make, model and horse power.

In case of center line thrust, no problem. Nothing requires the two engines to be the same. Not even weight and balance. Burt Rutan's Voyager is an example. You can find that the front engine is different from the rear engine.

It might not be because of the reason described above, but if you are into auto conversions and designing a twin, how you plan to get two identical engines for not much cost at all (from totalled cars for example). Might prove to be a challenge, especially in a country like Finland where the population and the availability of engines might be poor. With center line thrust you can use different engines in the front and rear.

By the way: Merry Christmas and Happy New Year!

Duborvnik Airport

Every other week European carriers are announcing that they are including Dubrovnik, located on Croatia’s Adriatic coast, in their destinations network. Tourism is the most obvious reason for flight operations with people, particularly from the European Union, wanting to travel direct from their city to Dubrovnik. However with careful planning and management even a long haul service could be profitable on a seasonal basis.

There is no direct air service to Milan and Nice. This, in spite of the increased number of tourists from the region. The number of people arriving by cars from these cities is significant and when translated into figures could become a profitable air service. There are many charter flights during the summer season flying from Dubrovnik to Paris. According to passenger figures, there is high demand for direct morning flights. These passengers use time-consuming intermediate airports to reach Paris. Lisbon, in Portugal, could become a profitable summer destination. Figures show that there are a large number of Portuguese visitors. Since there is no direct connection, they use indirect flights to reach Dubrovnik and the rest of the region. Slovenians are ranked very high on the list of visitors to Dubrovnik according to figures submitted by the Dubrovnik Tourist Board, but with no air service, the only option is to arrive by road. Other destinations inside Europe that can be proved profitable due to high demand include Moscow, St. Petersburg, Salzburg, Venice, Hamburg, Warsaw, Berlin, Athens, Istanbul and Budapest.
More than 3.000 passengers travelled to Dubrovnik from New York in 2008. In the 1980s there was daily direct service between the two cities and this has not resumed despite demand evidence. Due to the fact that the situation in the 80s was much different, today this service could be made profitable with scheduled charter flights during the summer.

Dubrovnik Airport offers an airport charge incentive programme for airlines interested in taking up new routes, additional frequencies, or year-round traffic. Besides financial support, the airport offers assisted advertising as well.

In January you can read more airport analysis that will be published on the blog.

I was wondering what kind of servos can be used with the Spektrum DX5E. The Spektrum servos on their website all seem to be micro foamy plane type servos, no standard size for say .40 size planes are shown. So if one is to buy this 2.4 Ghz radio / receiver, is it compatible with standard Futaba servos? A switch harness and battery pack would also be needed to complete the radio package, correct?

I think I paid about $350 for me DX7 fully loaded back in March. The TX that came with my Blade CX2 is a 5 Channel DSM probably close in features as the DX5E, no programming features though. Both have been flawless in their operation so far. Are you able to field program the DX5E?

Central Zagreb

For all readers celebrating Christmas today we wish you a Merry Christmas!

Sretan Božić
Vesel Božić

Visit tomorrow for an analysis of potential destinations from Dubrovnik, Croatia.

Waiting for government - Jat Airways

Frustration is growing at Jat Airways due to the fact that the Serbian government has still not decided whether it will help the struggling carrier after its privatisation process failed earlier in the year. Workers at Jat who found their paycheques slashed by 10% this month are threatening that they will begin protests during the New Year and Christmas holiday period which could derail air transportation in the country. Jat will increase frequencies to popular destinations during the holiday period if strike action does not go ahead.

The Serbian government promised it would provide funds so the airline could compensate 700 excess workers to leave the airline. Jat would return the provided credit by next fall however the government has not provided the funds yet. Due to the fact that the funds were not provided, the 700 workers cannot leave until spring 2009 because they first must use their entire 2009 holiday time. Saša Vlaisavljević, Jat’s CEO, released a short statement stating “We are waiting for the government to react. We no longer have time”.

Couple of new ones (for me at least) parked at Ardmore 23Dec.

Jabiru ZK-CPA has been around since May 2003 and is currently registered to a Mr Boag of Palmerston North.

Cessna T210M Centurion ZK-ZIO came onto the register 11Dec this year and was previously registered N6298B with it arriving into New Plymouth via container and noted Labour Weekend marked as ZIO. Its registered to John Sturgess & Associates of Manukau. The addition of ZIO to the register brings the population to 8.

Crisis in Adria? Not in 2008

Slovenian flag carrier Adria Airways expects an operating profit of 1.9 million Euros in 2008 despite the global economic crisis that the aviation industry has been caught in. This is a good million less than in 2007, although the number of passengers is expected to increase by 17% to 1.3 million by the end of 2008, while European growth is four times lower. High oil prices cost the company an additional 11 million Euros, the flag carrier wrote in a press release after the session of the company's management and supervisors last Friday. Adria's income will exceed 200 million Euros, which is 13% more than in 2007 and 5% above the estimated levels. The company retained operational liquidity throughout the year, while cash flow will finish at 32 million Euros, the press release says. The supervisors confirmed the plan for 2009, which forecasts no increase in the number of passengers due to the financial crisis. The management presented additional measures, which it is preparing to rationalise operations in order to achieve a positive result despite the expected recession, the company wrote.