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Old 9th Sep 2012, 16:12
  #90 (permalink)  
Rod1
 
Join Date: Apr 2003
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"the Aquila felt like a microlite"

As I said in an early post it is mostly a matter of wing loading not weight. I did the following some time ago and am not suggesting any of the machines are suitable for you but thought the comparison may be of interest.

You will see that the PiperSport (SC) is the heaviest aircraft but has a much lower wing loading than the comparison machines;

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Comparing aircraft numbers is an interesting pastime and can be useful to sort the facts from the fiction. The Sportcruiser was designed to meet the US LSA cat, but most of the SC aircraft in the UK are flying based on compliance with CS-VLA. If we compare the SC with other VLA machines we get some interesting results;

“The aircraft is very light (~380kgs Empty mass, 600kgs MAUW)”

Compared with a 152 (1950’s tec) it is light, compared with the modern VLA designs it is very heavy. This is probably due to the use of traditional metal construction. Some comparisons;

SC 380kg
Pioneer 300 305kg
MCR01 Club 250kg

All three use the same Rotax 912 100hp engine, so the power to weight ratio is very different, which of course has a big impact on performance;

SC Cruise 105 kts ~ 18 lts/hr
Pioneer Cruise 135 kts ~ 18.5 lts/hr
MCR01 Club Cruise 138 kts ~ 18.5 lts/hr

So the aircraft is about 40% slower. This of course will mean you need a lot more fuel to travel the same distance, so can the CS carry the extra fuel?

SC 120L
Pioneer 80L
MCR01 80L

So the lack of speed can be compensated by fuel capacity, but can it lift the weight?

SC 220kg
Pioneer 201kg
MCR01 Club 240kg

Certainly any advantage of the fuel capacity is seriously compromised by the speed / load equation. How Comfortable? The SC is a much bigger aircraft than the others, so what about cockpit width?

SC 46.5”
Pionear 41.3”
MCR01 44.5”

A clear win for the SC, but there is another issue with how Comfortable an aircraft is. How much do you get bounced around on an average UK summers day? This is not just about weight; it is also about wing area;

CS 13.2 Msq
Pioneer 10 Msq
MCR01 6.5 Msq

The key issue being wing loading;

CS 45 kg/sq
Pioneer 56 kg/sq
MCR01 75 kg/sq

Of all the aircraft above, the SC is the most likely to have to slow down in turbulence, but does the large wing give it an advantage in stall speed?

SC 38kn
Pioneer 44kn
MCR01 42kn

So a clear win for the SC, which should allow it to use a bit less runway; I cannot find a full set of figures on that, but it is almost certainly true.

Crosswind limit?

CS Anyone?
Pioneer 20kn
MCR 20Kn

Rate of Climb?

CD 1200 fpm
Pioneer 1500 fpm
MCR01 1600 fpm


Rod1
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