Flying the Auster.
Red On, Green On
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BS pilot - what was the octane value of the fuel used in 1946, compared to today's fuel, and would that make a difference to power?
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Auster Juice
airborne_artist,
In my handling notes, the fuel is given as, "normally 73 octane, or unleaded fuel of any octane number up to 80".
Octane is only an anti-knock rating. So fuelling the aircraft on 100LL would probably allow the engine to be worked harder at a higher altitude than on 73 to 80 octane because the onset of knocking (detonation) would probably be delayed.
It would not provide 10 more b.h.p.
regards,
Broomstick.
In my handling notes, the fuel is given as, "normally 73 octane, or unleaded fuel of any octane number up to 80".
Octane is only an anti-knock rating. So fuelling the aircraft on 100LL would probably allow the engine to be worked harder at a higher altitude than on 73 to 80 octane because the onset of knocking (detonation) would probably be delayed.
It would not provide 10 more b.h.p.
regards,
Broomstick.
Broomstickpilot they are photocopies of the original Blackburn manual but I am relying on a memory that has been prven wrong before! Using the same memory, isn't the Cirrus I rated at 90 hp and the II / IIA at 100hp? My Minor II still pulls the required 2,050 rpm for the run up and comes pretty close to the book climb / cruise figures so it should be producing fairly close to it's rated horsepower.
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Stolen from Wikipedia:
Cirrus Engine was a British aircraft engine manufacturer, known for their line of 4-cylinder air-cooled inline engines for general aviation use. The company was bought by Blackburn Aircraft in 1934, and operated as a separate division until production ended in the post-WWII era.
Cirrus's first product was the 90 hp (67 kW) Cirrus Minor, which passed its 50 hour type rating in 1925. It was the first air-cooled inline engine, a design that proved extremely popular for light aircraft. The basic layout was quickly copied by a number of other manufacturers.
The Minor was known for excellent reliability, and had a major "win" when it was selected to power the RAF's Auster observation aircraft. The RAF's version had several modifications, known as the Series I. Although externally identical, the Series II engine was redesiged to operate on 77 octane fuel, as opposed to the original's 70, increasing power to 100 hp (75 kW).
And even more amazingly you can buy an 18cc replica of it for your model!!
Enjoy your Austering! And look after that antique dragging you airward!
Cirrus Engine was a British aircraft engine manufacturer, known for their line of 4-cylinder air-cooled inline engines for general aviation use. The company was bought by Blackburn Aircraft in 1934, and operated as a separate division until production ended in the post-WWII era.
Cirrus's first product was the 90 hp (67 kW) Cirrus Minor, which passed its 50 hour type rating in 1925. It was the first air-cooled inline engine, a design that proved extremely popular for light aircraft. The basic layout was quickly copied by a number of other manufacturers.
The Minor was known for excellent reliability, and had a major "win" when it was selected to power the RAF's Auster observation aircraft. The RAF's version had several modifications, known as the Series I. Although externally identical, the Series II engine was redesiged to operate on 77 octane fuel, as opposed to the original's 70, increasing power to 100 hp (75 kW).
And even more amazingly you can buy an 18cc replica of it for your model!!
Enjoy your Austering! And look after that antique dragging you airward!
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Cirrus Minor II Engine
Hi LowNSlow,
Thanks for your response.
However, there you are. Gasax has come up with the goods: thanks gasax.
It would appear that when you apply that last half inch of travel on the throttle lever, and the engine switches over from 'hot air' to 'cold air', and the extra petrol jet cuts in, and you get that last fifty revs, she is giving you 100 b.h.p.
Good old girl!
Broomstick.
Thanks for your response.
However, there you are. Gasax has come up with the goods: thanks gasax.
It would appear that when you apply that last half inch of travel on the throttle lever, and the engine switches over from 'hot air' to 'cold air', and the extra petrol jet cuts in, and you get that last fifty revs, she is giving you 100 b.h.p.
Good old girl!
Broomstick.
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This can often show a significant increase in bhp.
Lister
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Cirrus Power rateing.
The little 'Blue Book" or owners manual has a statement similar to : Maximum revs is 2600rpm for five min. which is the 100hp rateing. Normal cruise is around the 2100rpm and will give approxmatly 85/90 hp.(Depends on prop pitch)
AIK came with a fully sterable tail wheel, I think of the Maul variety, and brings the back of the aircraft up slightly and may give a better forward view.
Have been told 35kts is a good landing speed with two notches of flap, tried the full flap landing, woah! was loosing it fast till the flaps came up.
I have just spent the last couple of months perfecting a fiberglass replica instrument pannel, full faceia, looks nice with a black hammer tone paint finish, even if I do say so myself. The old pannel has more holes and gaps in it than a drafty motor bike.
AIK came with a fully sterable tail wheel, I think of the Maul variety, and brings the back of the aircraft up slightly and may give a better forward view.
Have been told 35kts is a good landing speed with two notches of flap, tried the full flap landing, woah! was loosing it fast till the flaps came up.
I have just spent the last couple of months perfecting a fiberglass replica instrument pannel, full faceia, looks nice with a black hammer tone paint finish, even if I do say so myself. The old pannel has more holes and gaps in it than a drafty motor bike.
