TR UAV/UCAV Programs | Anka - series | Kızılelma | TB - series

Zafer

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Thas
Mayber PG-115 didn't meet their standards.
That is a possibility as the Rotax is the top quality engine with %80 market share in its class. It is not easy to match that quality in a short time. Still the performance TEI put out with PD170 is an indication of what we can expect from TEI for the PG115. They probably need more time.
 

Profchaos

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Hi guys.when i was searching for the specifications of the AI 450 ukrainian engine that akinci is going to use, i saw that its dry weight is around 130 kg.so these 450 hp engines are a lot less heavy compared to 170 hp tei pd170 which is around 160 kg.why is pd170 underperformes this much?
 

what

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I think that there should be one thread per drone company or even drone line to make things a bit easier to follow. What do you guys think?
 

Test7

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Hi guys.when i was searching for the specifications of the AI 450 ukrainian engine that akinci is going to use, i saw that its dry weight is around 130 kg.so these 450 hp engines are a lot less heavy compared to 170 hp tei pd170 which is around 160 kg.why is pd170 underperformes this much?

Because Pd170 is a piston engine, Al-450 is a turboprop engine. So one is an apple and the other is a pear.

Piston vs. Turboprop: Efficiency

Piston engines and turboprops are both internal combustion engines that must compress air, burn that air using fuel and expel the resulting exhaust gas. The thermodynamic properties that govern these engines result in interesting compromises between the two systems.

Generally speaking, turbine engines lose efficiency as they become smaller while piston engines become less efficient as they grow larger.

As an example, consider the following engines and their respective fuel flows at typical cruise power settings.

1.png

Typical Piston and Turboprop Cruise Efficiencies


Before digging too deeply into the chart above, it is worth noting some details. The data above is representative, and non-specific to a particular aircraft, and represents typical values only.

Turboprop engine cruise data is more typically referenced with respect to torque output, but for the sake of direct comparison horsepower values are used.

Finally, the data above is for maximum continuous cruise, not for reduced power settings, this flight condition was selected to represent maximum performance of the engine.

2.png

Lycoming IO-720

3.png

Pratt and Whitney PT6A

Fuel Flow and Specific Fuel Consumption​

Using a cursory review of the data above, the raw fuel flow values are misleading. The Lycoming engines appear to hold the advantage in terms of pure fuel flow, besting the PT6A-21 by at least 11 gallons per hour.

Closer inspection however reveals that the specific fuel consumption or Gal/Hr/HP value favors the IO-550 and the PT6A-60A. At the extremes of the power output ranges, efficiency is dramatically improved, the engines burn less fuel per hour to generate a given power output.

It is apparent that at some point larger and larger piston engines become less efficient relative to similarly sized turbine engines, and conversely, smaller turbines become less efficient than similarly sized pistons.

The exact crossover point where this happens is somewhat dependent on the particular installation and the mission profile of the aircraft.

Fuel Costs

Finally, discussion of cost would be incomplete without a discussion of fuel costs. Referencing AirNav.com average fuel price data as of December 2019, 100LL fuel (avgas) averages $5.06/gallon and Jet-A averages $4.68/gallon (see our article on “Why does jet fuel cost less than 100LL?”).

Applying these averages to the fuel burn data above in table 1 the
following direct fuel costs result:
4.png


It is again evident that the turboprop engines command a premium with regard to direct fuel costs at the “low” end of the power range; however, that margin narrows as the power output of the turboprop engines increases.

This is a direct result of the improved thermal efficiency of turboprop engines. This fact again makes the operating costs of small turboprop engines difficult to justify in small aircraft such as the Beechcraft Bonanza or the Cessna 206 Stationair.

Ultimately for both types of engines, operating cost is managed by good engine operating habits and by proper maintenance and inspection intervals.

The most reliable piston engines and most reliable turboprop engines are those that are properly managed as the complex and expensive equipment that they are. While piston engines have a greater number of direct wear parts, it is generally simpler and less expensive to service those wear parts.

Replacing a cam or a valve is generally a straight forward exercise for a piston engine, while accessing and replacing a turbine blade is substantially more difficult and expensive proposition in a turboprop engine.

Piston vs. Turboprop: Performance

Piston engine performance and turboprop performance, while similar in some respects, is an illustration of the benefits of turbine engine operating characteristics. The performance envelope of a given engine is best described by cruise performance and takeoff performance.

In the case of both piston and turboprop engines, total power output is measured in horsepower, and the engine will be capable of generating maximum continuous power up to a “critical altitude;” above which, performance is reduced.
 

Reviewbrah

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Because Pd170 is a piston engine, Al-450 is a turboprop engine. So one is an apple and the other is a pear.

Piston vs. Turboprop: Efficiency

Piston engines and turboprops are both internal combustion engines that must compress air, burn that air using fuel and expel the resulting exhaust gas. The thermodynamic properties that govern these engines result in interesting compromises between the two systems.

Generally speaking, turbine engines lose efficiency as they become smaller while piston engines become less efficient as they grow larger.

As an example, consider the following engines and their respective fuel flows at typical cruise power settings.

View attachment 5858
Typical Piston and Turboprop Cruise Efficiencies


Before digging too deeply into the chart above, it is worth noting some details. The data above is representative, and non-specific to a particular aircraft, and represents typical values only.

Turboprop engine cruise data is more typically referenced with respect to torque output, but for the sake of direct comparison horsepower values are used.

Finally, the data above is for maximum continuous cruise, not for reduced power settings, this flight condition was selected to represent maximum performance of the engine.

View attachment 5859
Lycoming IO-720

View attachment 5860
Pratt and Whitney PT6A

Fuel Flow and Specific Fuel Consumption​

Using a cursory review of the data above, the raw fuel flow values are misleading. The Lycoming engines appear to hold the advantage in terms of pure fuel flow, besting the PT6A-21 by at least 11 gallons per hour.

Closer inspection however reveals that the specific fuel consumption or Gal/Hr/HP value favors the IO-550 and the PT6A-60A. At the extremes of the power output ranges, efficiency is dramatically improved, the engines burn less fuel per hour to generate a given power output.

It is apparent that at some point larger and larger piston engines become less efficient relative to similarly sized turbine engines, and conversely, smaller turbines become less efficient than similarly sized pistons.

The exact crossover point where this happens is somewhat dependent on the particular installation and the mission profile of the aircraft.

Fuel Costs

Finally, discussion of cost would be incomplete without a discussion of fuel costs. Referencing AirNav.com average fuel price data as of December 2019, 100LL fuel (avgas) averages $5.06/gallon and Jet-A averages $4.68/gallon (see our article on “Why does jet fuel cost less than 100LL?”).

Applying these averages to the fuel burn data above in table 1 the
following direct fuel costs result:
View attachment 5861

It is again evident that the turboprop engines command a premium with regard to direct fuel costs at the “low” end of the power range; however, that margin narrows as the power output of the turboprop engines increases.

This is a direct result of the improved thermal efficiency of turboprop engines. This fact again makes the operating costs of small turboprop engines difficult to justify in small aircraft such as the Beechcraft Bonanza or the Cessna 206 Stationair.

Ultimately for both types of engines, operating cost is managed by good engine operating habits and by proper maintenance and inspection intervals.

The most reliable piston engines and most reliable turboprop engines are those that are properly managed as the complex and expensive equipment that they are. While piston engines have a greater number of direct wear parts, it is generally simpler and less expensive to service those wear parts.

Replacing a cam or a valve is generally a straight forward exercise for a piston engine, while accessing and replacing a turbine blade is substantially more difficult and expensive proposition in a turboprop engine.

Piston vs. Turboprop: Performance

Piston engine performance and turboprop performance, while similar in some respects, is an illustration of the benefits of turbine engine operating characteristics. The performance envelope of a given engine is best described by cruise performance and takeoff performance.

In the case of both piston and turboprop engines, total power output is measured in horsepower, and the engine will be capable of generating maximum continuous power up to a “critical altitude;” above which, performance is reduced.

Additional info for reference

D5gum5GX4AAQfxS.jpg


PD-170



Dy9wVIUX4AELC2Y.jpg
 
Last edited:

Zafer

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There are other aspects to engine preference like failure modes. While piston engine can seize and stop a turbine will still continue providing power dying gradually over time.
 

Ryder

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It was claimed that Bayraktar TB2’s belonging to the Ukrainian Army started their first attacks against the DNR and LNR separatist terrorist groups in Donbass, and the targets were neutralized by sensitive hits.
Ukraine has been training and exercising with TB2s for ~ 1.5 years.

Any chance of Ukraine taking back Crimea??

Hopefully with Turkish drones leading the way. Russians cant stay there forever.
 

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