Crash Landing in Cunnamulla - two hurt.
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Well, as I understand that, endurance is how long the donks will keep turning, which might be important if I was oh say up looking for a 777, but if I wanted to fly a long range flight like say YLIL-YCMU in one hop I'd rather care about how far I could go (with thrust) not how long it took. But thats just me.
Last edited by Hempy; 27th Mar 2014 at 11:10.
Hempy
Be careful listening to Trent.
‘Endurance’ is indeed about ‘how long the donks will keep turning’.
But there are many variables that affect when the donks will ‘stop turning’ and how far down track the aircraft to which they are fitted will be when they do.
The donk in question in this thread is one fitted to a Warrior.
Let’s assume 25 knots headwind
Lowest drag IAS in a Warrior at MTOW is about 80 knots.
Apply a headwind of 25 knots and assume our adjusted-for-headwind best range IAS is 85, for a ground speed of 60kts. (Trent (correctly) says that the adjusted speed should be around 92, but let’s not complicate things at this point by making assumptions in my theory’s favour. We could complicate things more by taking into account changing weights and climb fuel consumption etc, but let’s not, at this point.)
500 nms at 60 knots is a very long way. At a constant 60 knots GS it would take 500 minutes or 8 hours and 20 minutes.
With 180 litres usable on board, you’d have to burn less than 22 litres an hour to make it.
And how much do you have to burn to maintain an IAS of 85 knots in a Warrior?
Well jigger me with a bargepole if it’s not: “Less than 22 litres an hour”! You wouldn’t land with much more than fumes - those operations are called “W8”.
Let’s assume no headwind
Given that the actual aircraft appears to have had a slight tailwind in real life, let’s assume it didn’t (because otherwise the assumption would be in my theory’s favour).
Best long range speed is the lowest drag speed for nil wind: That’s 80 knots.
500 nms (on the same assumptions) is 6 hours and 15 minutes.
With 180 litres on board, you’d have to burn less than 28 litres per hour to land with fuel.
To maintain 80 kts IAS in a Warrior, you don’t have to burn anywhere near 28 litres per hour.
Trent will hopefully help us out by explaining where and why my calculations are wrong, rather than merely asserting they are “wrong”.
Be careful listening to Trent.
‘Endurance’ is indeed about ‘how long the donks will keep turning’.
But there are many variables that affect when the donks will ‘stop turning’ and how far down track the aircraft to which they are fitted will be when they do.
The donk in question in this thread is one fitted to a Warrior.
Let’s assume 25 knots headwind
Lowest drag IAS in a Warrior at MTOW is about 80 knots.
Apply a headwind of 25 knots and assume our adjusted-for-headwind best range IAS is 85, for a ground speed of 60kts. (Trent (correctly) says that the adjusted speed should be around 92, but let’s not complicate things at this point by making assumptions in my theory’s favour. We could complicate things more by taking into account changing weights and climb fuel consumption etc, but let’s not, at this point.)
500 nms at 60 knots is a very long way. At a constant 60 knots GS it would take 500 minutes or 8 hours and 20 minutes.
With 180 litres usable on board, you’d have to burn less than 22 litres an hour to make it.
And how much do you have to burn to maintain an IAS of 85 knots in a Warrior?
Well jigger me with a bargepole if it’s not: “Less than 22 litres an hour”! You wouldn’t land with much more than fumes - those operations are called “W8”.
Let’s assume no headwind
Given that the actual aircraft appears to have had a slight tailwind in real life, let’s assume it didn’t (because otherwise the assumption would be in my theory’s favour).
Best long range speed is the lowest drag speed for nil wind: That’s 80 knots.
500 nms (on the same assumptions) is 6 hours and 15 minutes.
With 180 litres on board, you’d have to burn less than 28 litres per hour to land with fuel.
To maintain 80 kts IAS in a Warrior, you don’t have to burn anywhere near 28 litres per hour.
Trent will hopefully help us out by explaining where and why my calculations are wrong, rather than merely asserting they are “wrong”.
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Ahem. YLIL - YBCV (via YBKE, only a couple of miles off track) is 677nm.
Want to run those numbers again! Oh, and you really should add a bit for reserves too!
ps
I'm glad to see your method now includes what you learned earlier today from being held to account for your lack of knowledge on the subject. You're getting there….. but very slowly..
pps
the "assumptions in my theories favour" gave me a little giggle too.
ppps. The figure of 220 nm short I gave earlier was just a spur of the moment guess, but I've since run some more realistic burn figures including climb and taxi burn and it came up with 211 nm short. Sorry about that sloppiness.
Want to run those numbers again! Oh, and you really should add a bit for reserves too!
ps
I'm glad to see your method now includes what you learned earlier today from being held to account for your lack of knowledge on the subject. You're getting there….. but very slowly..
pps
the "assumptions in my theories favour" gave me a little giggle too.
ppps. The figure of 220 nm short I gave earlier was just a spur of the moment guess, but I've since run some more realistic burn figures including climb and taxi burn and it came up with 211 nm short. Sorry about that sloppiness.
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No spats!
Don't forget to take the 7 knots off, or make an adjustment to your fuel burn calcs!
edit
ISA +10 for performance calcs would be a fair temperature I think. Bourke info provided as an average for the cruise portion, but I'm not really that fussy if you don't want to.
Last edited by Trent 972; 27th Mar 2014 at 13:46.
You’re being very naughty, Trent. 
The report says the plan was to refuel at Bourke. (You have read the report, haven’t you? That’s the second time I’ve asked that question…)
The ‘best range’ speed for CCQ is what it is (was). It is (was) determined by the laws of physics, and therefore the outcome is the same, whether or not the planned destination is Charleville, Chicago or Chittagong.
Arguing about what the best range speed for CCQ may have been, and whether it’s a good idea for CCQ to have been operated at that speed, seems to me to be a pointless exercise.
The report says the plan was to refuel at Bourke. (You have read the report, haven’t you? That’s the second time I’ve asked that question…)
The ‘best range’ speed for CCQ is what it is (was). It is (was) determined by the laws of physics, and therefore the outcome is the same, whether or not the planned destination is Charleville, Chicago or Chittagong.
Arguing about what the best range speed for CCQ may have been, and whether it’s a good idea for CCQ to have been operated at that speed, seems to me to be a pointless exercise.
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Creampuff, so when you said
You were wrong.
and again when I challenged you to consider a theoretical 25 knot H/W component you said
You were wrong again.
Again then you said
You were really wrong.
and still you say
DOH again
and Lastly you resort to the petulant child defence.
On the matter of 'Long Range Flying', you have been weighed and measured and come up a bit short.
I'd suggest you get back to J. Deakin and ask him to finish off that quote on how to extend your range in a Headwind, because you've grabbed the bull by the horns and gone off half cocked there old fella. (mixed metaphor intentional), and yes I have read the report.
And to get back to the subject of this thread, none of this was considered by the PIC of CCQ. Had the aircraft been flown at the IAS for minimum drag, whether or not it was adjusted a couple of knots for the wind component, the aircraft would have made it with fuel to spare.
and again when I challenged you to consider a theoretical 25 knot H/W component you said
If he’d flown at the IAS for least drag, adjusted or not for wind component, he would have made it with fuel to spare.
Again then you said
I stand by my statement that had CCQ been flown at the IAS for minimum drag, whether or not it was adjusted a couple of knots for the wind component, the aircraft would have made it with fuel to spare. Lots of fuel to spare.
and still you say
You wouldn’t land with much more than fumes - those operations are called “W8”.
and Lastly you resort to the petulant child defence.
On the matter of 'Long Range Flying', you have been weighed and measured and come up a bit short.
I'd suggest you get back to J. Deakin and ask him to finish off that quote on how to extend your range in a Headwind, because you've grabbed the bull by the horns and gone off half cocked there old fella. (mixed metaphor intentional), and yes I have read the report.
Had CCQ been flown at the IAS for minimum drag, whether or not it was adjusted a couple of knots for the wind component, the aircraft would have made it with fuel to spare. Lots of fuel to spare.
There was no headwind.
Anyway, great initiative Jabba!
We should do these analyses for ATSB more often.
There was no headwind.
Anyway, great initiative Jabba!
We should do these analyses for ATSB more often.
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There you have it folks.
Be very very careful with what some people on this forum will tell you.
Creampuff huffed and puffed but he couldn't blow the house down.
I challenged him on his statement that a headwind doesn't affect the IAS for max range flying and he offered nothing but deflection and misinformation.
Educational value zero.
Edit- Creampuff said
Hahahahahahahahahahaha.
pm that I received from Creampuff
No Creampuff, it's because you were WRONG with what you wrote, and yet you continued to bullsh!t on, knowing that you were WRONG.
PS. Please stop having sexual thoughts about me, NO means NO.
I am not interested in you like that, or any other way. P!ss off weirdo!
Be very very careful with what some people on this forum will tell you.
Creampuff huffed and puffed but he couldn't blow the house down.
I challenged him on his statement that a headwind doesn't affect the IAS for max range flying and he offered nothing but deflection and misinformation.
Educational value zero.
Edit- Creampuff said
We should do these analyses for ATSB more often.
pm that I received from Creampuff
Greetings!
So help me out, Trent.
Did I get a job you wanted, sleep with your girlfriend, wife or a hot chick you never got to root?
Why are you so obsessed by just one of the many mistakes that, like you, I make every day?
It's hard to fathom the cause (unless you are just a garden variety nutjob).
So help me out, Trent.
Did I get a job you wanted, sleep with your girlfriend, wife or a hot chick you never got to root?
Why are you so obsessed by just one of the many mistakes that, like you, I make every day?
It's hard to fathom the cause (unless you are just a garden variety nutjob).
PS. Please stop having sexual thoughts about me, NO means NO.
I am not interested in you like that, or any other way. P!ss off weirdo!
Last edited by Trent 972; 31st Mar 2014 at 12:03. Reason: WooHoo - I've got a stalker.
