Lets make a helicopter
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Just as a thought hopefuly in the right general direction, how about the idea of incorporation of already proven parts or subsystems as a possible route to some degree of cost saving.
The specific direction I'm thinking would be using something like the Firescout UAV as either a starting concept or even going as far as thinking of incorporation of subsystems ie rotor system, drivetrain.
Maybe I'm miles off, maybe it has possibilities. Either way worth a look perhaps ?
The specific direction I'm thinking would be using something like the Firescout UAV as either a starting concept or even going as far as thinking of incorporation of subsystems ie rotor system, drivetrain.
Maybe I'm miles off, maybe it has possibilities. Either way worth a look perhaps ?
Handy,
It's a very good point and one that has been made privately by a number of people. Technically, there are obvious advantages to including existing and proven hardware into a budget design; it reduces the development time and cost and gives you a high degree of confidence that the machine will work properly. However, components from certified aircraft or derivatives of certified aircraft are not cheap. Maybe someone here can tell us what three blades from a S333 cost, maybe even the cost of the hub. My guess is those components alone would cost as much as a Rotorway!
Aside from this, would a reputable manufacturer want to risk there reputation on such a venture? If it was successful would they want to risk losing sales to private owners?
Although clear benefits exist for incorporating existing hardware into the design the cost and willingness of other companies to co-operate are likely to render it impossible but it would certainly be worth running it past them.
CRAN
It's a very good point and one that has been made privately by a number of people. Technically, there are obvious advantages to including existing and proven hardware into a budget design; it reduces the development time and cost and gives you a high degree of confidence that the machine will work properly. However, components from certified aircraft or derivatives of certified aircraft are not cheap. Maybe someone here can tell us what three blades from a S333 cost, maybe even the cost of the hub. My guess is those components alone would cost as much as a Rotorway!
Aside from this, would a reputable manufacturer want to risk there reputation on such a venture? If it was successful would they want to risk losing sales to private owners?
Although clear benefits exist for incorporating existing hardware into the design the cost and willingness of other companies to co-operate are likely to render it impossible but it would certainly be worth running it past them.
CRAN
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thanks Cran
check this : http://www.helips.com
these guys are serioursly challenging big parts of the market..
and hen you look at who they are, i feel like a very very little worm...
don't think i'm a downer, some people here know what it try to build.
thanks
check this : http://www.helips.com
these guys are serioursly challenging big parts of the market..
and hen you look at who they are, i feel like a very very little worm...
don't think i'm a downer, some people here know what it try to build.
thanks
Thanks for the head's-up zeeoo, unfortunately I don't speak any French whatsoever! What ever happened to Bruno Guimbal's 2-seat machine the Cabri G2? Any ideas?
Any chance of an English summary?
Cheers
CRAN
Any chance of an English summary?
Cheers
CRAN
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oops Cran, sorry, don't cry for the language 
, cry for the aircraft they are going to develop 
you're right, i found this site searching for guimbal's two seat to have info about the rotor.
his helicopter has flown fine as far as i know, and i suspect he is a part of the helips crew (they are all ex-eng from aerostatiale-eurocopter) and his "cabri" may be in the backyard
.
I think that, if they go into business, an english version will be mandatory.
cheers
, cry for the aircraft they are going to develop you're right, i found this site searching for guimbal's two seat to have info about the rotor.
his helicopter has flown fine as far as i know, and i suspect he is a part of the helips crew (they are all ex-eng from aerostatiale-eurocopter) and his "cabri" may be in the backyard
.I think that, if they go into business, an english version will be mandatory.
cheers
Zeeoo,
I don't think there is any need to reach for the cyanide just yet! I have seen many, many projects like this come and go without ever bringing anything to market!
We will have to wait and see.
CRAN
I don't think there is any need to reach for the cyanide just yet! I have seen many, many projects like this come and go without ever bringing anything to market!
We will have to wait and see.
CRAN
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You're right Cran... time will tell, but i think eurocopter funds a part of their activity as they are retired.
For your colllective project, go ahead and like others told me : "GET BUSY".
I will not be a basher, but i like to tickle statements just like others like to tickle mine (positively).
good luck to all of you and : wrenches up !!
cheers
For your colllective project, go ahead and like others told me : "GET BUSY".
I will not be a basher, but i like to tickle statements
just like others like to tickle mine (positively).good luck to all of you and : wrenches up !!
cheers
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Humorously;
(1) RELIABILITY & SAFETY
(2) CRASHWORTHY AIRFRAME
(3) LOW, LOW COST
(4) SIMPLE LOW MAINTAINANCE REQUIREMENTS
(5) PERFORMANCE
(6) APPEARANCE & FIXTURES
Seriously;
If the intent is to end up with a slightly improved rotorcraft, consider buying a used Robinson R-22 or Rotorway and then start modifying it.
~ alternatively ~
If the intent is to end up with the lowest cost rotorcraft, consider buying a used Robinson R-22 or Rotorway and then doing nothing to it.
~ alternatively ~
If the intent is to end up with a better rotorcraft, consider buying a box and then stepping outside of it.
Without one or more significant improvements, any new rotorcraft will be, at the best, nothing more than just another one amongst the few. IMHO, any significant improvement to rotorcraft must start by improving the rotor of the craft. The fuselage and the engine are secondary appendages that hang from the rotor.
(1) RELIABILITY & SAFETY
(2) CRASHWORTHY AIRFRAME
(3) LOW, LOW COST
(4) SIMPLE LOW MAINTAINANCE REQUIREMENTS
(5) PERFORMANCE
(6) APPEARANCE & FIXTURES
Seriously;
If the intent is to end up with a slightly improved rotorcraft, consider buying a used Robinson R-22 or Rotorway and then start modifying it.
~ alternatively ~
If the intent is to end up with the lowest cost rotorcraft, consider buying a used Robinson R-22 or Rotorway and then doing nothing to it.
~ alternatively ~
If the intent is to end up with a better rotorcraft, consider buying a box and then stepping outside of it.
Without one or more significant improvements, any new rotorcraft will be, at the best, nothing more than just another one amongst the few. IMHO, any significant improvement to rotorcraft must start by improving the rotor of the craft. The fuselage and the engine are secondary appendages that hang from the rotor.
Last edited by Dave_Jackson; 20th Nov 2004 at 22:38.
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hi dave,
your answer is surprising to me, i know you're a rotor man but... IMNHO, for me, it is a all in one project.
you can have the better rotor, but desserved by a bad/heavy/costy engine it is a looser.
Same thing with the fuselage.
if some drivers love to know their car has the last generation "Xmagic", a lot just like to feel good in a comfortable car.
Depends on who the project targets : a mech enthusiast or a final user.
The genius of a good invention is that it can be forgotten by the user.
thank you
your answer is surprising to me, i know you're a rotor man but... IMNHO, for me, it is a all in one project.
you can have the better rotor, but desserved by a bad/heavy/costy engine it is a looser.
Same thing with the fuselage.
if some drivers love to know their car has the last generation "Xmagic", a lot just like to feel good in a comfortable car.
Depends on who the project targets : a mech enthusiast or a final user.
The genius of a good invention is that it can be forgotten by the user.
thank you
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zeeoo
Your points are valid.
You say; "Depends on who the project targets : a mech enthusiast or a final user."
My first post in this thread was " As an initial step, what about developing an acceptable list of the desired uses for this helicopter?". The response was underwhelming.
You say; "you can have the better rotor, but served by a bad/heavy/costly engine it is a looser."
Currently, the statements ' a cheap reliable rotorcraft' and 'a lightweight reliable reciprocating engine' are both oxymorons. But, the rotor design is in the domain of the rotorcraft manufacture. With limited exception, the engine is a buyout, and every helicopter manufacture selects what they feel is the best available engine, at the time, for their craft.
The current target of this thread is the Robinson R-22 yet the proposed engine is basically the same one that Robinson uses. This does not represent a price or a performance advantage. The advantage must come from the rotor (or rotors 
).
Your points are valid.
You say; "Depends on who the project targets : a mech enthusiast or a final user."
My first post in this thread was " As an initial step, what about developing an acceptable list of the desired uses for this helicopter?". The response was underwhelming.
You say; "you can have the better rotor, but served by a bad/heavy/costly engine it is a looser."
Currently, the statements ' a cheap reliable rotorcraft' and 'a lightweight reliable reciprocating engine' are both oxymorons. But, the rotor design is in the domain of the rotorcraft manufacture. With limited exception, the engine is a buyout, and every helicopter manufacture selects what they feel is the best available engine, at the time, for their craft.
The current target of this thread is the Robinson R-22 yet the proposed engine is basically the same one that Robinson uses. This does not represent a price or a performance advantage.
The advantage must come from the rotor (or rotors ).
A couple of technical points.
Firstly Tandem seating isn't that hard to achieve, you put the Captain's (student's) seat in the front so that - which will always be occupied, will always have a similar effect on CG. The second seat and fuel - which will vary considerably more, must be located as near as possible within the CG range. Look at any 1930s tandem fixed wing aeroplane such as the Tiger Moth for an example of this.
Secondly, I hate Lycoming engines - they are 1940s technology, too heavy, too expensive, and too thirsty. If I were picking an engine for a new "from scratch" helicopter design, if I could get away with under 120hp I'd look at the Rotax 914 (which is available certified) , but beyond that I'd look seriously at one of the new breed of lightweight turboprop/turboshaft engines such as the Walter 601 (also http://www.east-air.com/tech/m601d.htm). Whilst I'm quite fond of them in fixed wing aircraft, I agree with others that 2-stroke isn't the way to go, the specific fuel consumption will be crippling for a rotary application.
G
Firstly Tandem seating isn't that hard to achieve, you put the Captain's (student's) seat in the front so that - which will always be occupied, will always have a similar effect on CG. The second seat and fuel - which will vary considerably more, must be located as near as possible within the CG range. Look at any 1930s tandem fixed wing aeroplane such as the Tiger Moth for an example of this.
Secondly, I hate Lycoming engines - they are 1940s technology, too heavy, too expensive, and too thirsty. If I were picking an engine for a new "from scratch" helicopter design, if I could get away with under 120hp I'd look at the Rotax 914 (which is available certified) , but beyond that I'd look seriously at one of the new breed of lightweight turboprop/turboshaft engines such as the Walter 601 (also http://www.east-air.com/tech/m601d.htm). Whilst I'm quite fond of them in fixed wing aircraft, I agree with others that 2-stroke isn't the way to go, the specific fuel consumption will be crippling for a rotary application.
G
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Dave
ok, if targetting the R22, begin with a list of "not to do"
personnally i would do a list of what is very good in some choppers, a quick try :
- rotor : eurocopter astar or tiger
- fuselage : ec120 or bk117 for aside.
k max , tiger , cobra for tandem (the straight lines and thick tail allow a simple and rigid structure.
- tail rotor : fenestron, no notar
- skids : ec120
- engine : no idea, depends on overall weight but piston could be cheaper than a turbine.
- avionics : a digital central, cheaper
tell me if you think i hijack your thread dave,
thank you
G,
it is a good spot
why not a morane renault ?
I read 914 cannot endure more than 5 minutes of supercharge, a turbo diesel engine can sustain turbo usage.
For G centering/compensating, a suggestion : use the battery in the tail, mounted on adjustable skids..
thanks
ok, if targetting the R22, begin with a list of "not to do"
personnally i would do a list of what is very good in some choppers, a quick try :
- rotor : eurocopter astar or tiger
- fuselage : ec120 or bk117 for aside.
k max , tiger , cobra for tandem (the straight lines and thick tail allow a simple and rigid structure.
- tail rotor : fenestron, no notar
- skids : ec120
- engine : no idea, depends on overall weight but piston could be cheaper than a turbine.
- avionics : a digital central, cheaper
tell me if you think i hijack your thread dave,
thank you
G,
it is a good spot
why not a morane renault ?
I read 914 cannot endure more than 5 minutes of supercharge, a turbo diesel engine can sustain turbo usage.
For G centering/compensating, a suggestion : use the battery in the tail, mounted on adjustable skids..
thanks
There's a Certified 914 operators manual here , this gives a MTOP of 84.5kW / 5,800 RPM / 114 hp, and an MCP of 73.5kW / 5,500 RPM / 100 hp. It doesn't say so, but I think that Rotax normally follow the general convention of MTOP as 5 minute power.
I've sat through a few presentations by Mark Wilksch, who knows a thing or two about diesels in flying machines. He's of the view that below about 120hp in a fixed wing a Diesel cannot compete on power:weight with a good 4-stroke SI engine such as the 912/914. I'd venture that because of the rather higher continuous power (and thus fuel consumption) requirements of a helicopter, that threshold power is going to increase. That said, if you are looking for a Diesel, the WAM 160 might be a good starting point.
G
I've sat through a few presentations by Mark Wilksch, who knows a thing or two about diesels in flying machines. He's of the view that below about 120hp in a fixed wing a Diesel cannot compete on power:weight with a good 4-stroke SI engine such as the 912/914. I'd venture that because of the rather higher continuous power (and thus fuel consumption) requirements of a helicopter, that threshold power is going to increase. That said, if you are looking for a Diesel, the WAM 160 might be a good starting point.
G
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Hi G
Your link looks interesting, i'm starving for a 100 HP model of this one. i stay beyond the 100 hp limitation of european mono-UL classification.
About small diesels, they weight more, but their power is effective even in altitude and the mass of fuel needed to perform the same path is less, so weight to power ratio is not so bad.
In my airclub, there are 2 kitplanes projects started (same model), both with the dieselis, actually the 2 engines are "secretly" modified by a school, i asked to see them but the owners where not here, so i couldnt have access to them.
they are GM-Opel 1.5 L dieselis, rated to 80-90 hp, i will try to post more.
Just a general consideration about innovation/copy :
Japan, after ww2 didn't have a strong industry and certainly not the actual technological advance. I only can speak for automotive, but in the beginning they had a simple attitude : copy the good existing designs (so came the myth or the photographer-jap), the japanese just spent a lot of time on the automotive exhibits and observed what solutions worked fine..pictured them and copied them.. tha R&D power came after.
i would suggest to do the same for an helicopter : observe and copy existing solutions.
for the rotor : copy the starflex, bruno Guimbal copied it (he is one of the dsigners of starflex BTW) and it just worked fine on his 2 seat Cabri..
I am not an engineer, so , i dont challenge other eng with new theories/ideas, i just ask my self "how can i do this in a simple way", and, not to be pedant but, somtimes, looking down, you find a nugget.
the good example is BD5 development team : they spent a lot of time and money to resolve shaft whirl and torsional resonnance.. when a simple mech told them "if i was me i'd mount a freewheel"..
Damn ! sometimes eng are so high that they dont see where they step...
(thanks andre for the link)
thanks
Your link looks interesting, i'm starving for a 100 HP model of this one. i stay beyond the 100 hp limitation of european mono-UL classification.
About small diesels, they weight more, but their power is effective even in altitude and the mass of fuel needed to perform the same path is less, so weight to power ratio is not so bad.
In my airclub, there are 2 kitplanes projects started (same model), both with the dieselis, actually the 2 engines are "secretly" modified by a school, i asked to see them but the owners where not here, so i couldnt have access to them.
they are GM-Opel 1.5 L dieselis, rated to 80-90 hp, i will try to post more.
Just a general consideration about innovation/copy :
Japan, after ww2 didn't have a strong industry and certainly not the actual technological advance. I only can speak for automotive, but in the beginning they had a simple attitude : copy the good existing designs (so came the myth or the photographer-jap), the japanese just spent a lot of time on the automotive exhibits and observed what solutions worked fine..pictured them and copied them.. tha R&D power came after.
i would suggest to do the same for an helicopter : observe and copy existing solutions.
for the rotor : copy the starflex, bruno Guimbal copied it (he is one of the dsigners of starflex BTW) and it just worked fine on his 2 seat Cabri..
I am not an engineer, so , i dont challenge other eng with new theories/ideas, i just ask my self "how can i do this in a simple way", and, not to be pedant but, somtimes, looking down, you find a nugget.
the good example is BD5 development team : they spent a lot of time and money to resolve shaft whirl and torsional resonnance.. when a simple mech told them "if i was me i'd mount a freewheel"..
Damn ! sometimes eng are so high that they dont see where they step...
(thanks andre for the link)
thanks
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One problem with the Starflex is life , many of the components are limited to 2200 hrs though with a much lighter helicopter I am sure the 4000 hr target could be met.
From a maintenance perspective target should be all inspections up to annual can be carried out by the Pilot .i.e you take your helicopter in to the shop once a year for routine maintenence .
All critical parts should be on condition and TBO for dynamic components ( hey lets include the engine too ) should be 4000 hrs.
From a maintenance perspective target should be all inspections up to annual can be carried out by the Pilot .i.e you take your helicopter in to the shop once a year for routine maintenence .
All critical parts should be on condition and TBO for dynamic components ( hey lets include the engine too ) should be 4000 hrs.
This thread has certainly caught people’s attention! Keep it up folks!
Dave,
In response to your comments first. I am quite an admirer of your intermesher work and so will say nothing to discount this, nor will I argue the point that the first priority for a rotorcraft manufacturer is to create a good rotorcraft ~ of whatever configuration necessary.
However we must again return to the first point I made on this thread:
WHAT ARE WE TRYING TO ACHIEVE? KIT (WITH POSSIBLE PATH TO CERTIFICATION) OR ENTRY LEVEL COMMERICAL HELICOPTER?
If it’s a new commercial helicopter then you are correct, as is zeeoo, that there must be a significant improvement over the existing products else you're going nowhere fast. (Pardon the pun) Such improvements would include:
- Engine Technology
- Rotor Technology
- Structures Technology
- Avionics & Systems Technology
However if it is a kit, then a substantially improved rotorcraft can be designed over the three (practical) competitors R-22, RW 162F and Safari, simply by employing the low risk, low cost and low time-to-market strategy that I suggested. The reason I suggested this in the first place was I felt that our community would benefit from a reliable, low cost kit helicopter that they could own and maintain themselves. Remember unless one was willing to pay for such a project themselves, then you have to be able to convince would-be sponsors/customers that you will deliver TO A REALISTIC DEADLINE and high-risk approaches are a sure-fire way to scare such people off; certainly in the UK.
In response to Genghis and Zeeoo regarding the engine discussions:
G: Believe me, I also detest the Lycoming engines and their knock-offs, but when you plumb the numbers into a helicopter performance analysis then you soon see that few engines come near them. You are right about using the Rotax, but at 100hp you’re looking at a high performance one-seater or a very low performance, low payload 2-seater. I'm not convinced that there is a market for such a machine...
However, these guys are: www.dynali.com
I am a big fan of the Wilksch engines, I think they are thoroughly well engineered and based on a sound concept. Unfortunately the 120 hp unit is only good for a one-seater and the 160 hp unit not ready yet and if it was I fear any 2-seat rotorcraft based on it would be both short of payload and performance, but its certainly viable. Your comments about the Walter engines are interesting, though with a BSFC of 0.65 lb/hp-hr that engine is certainly not 'contemporary technology', an aero-engine of that size should easily achieve 0.45 lb/hp-hr with today’s technology!
Zeeoo, those Opel-GM 1.5l diesels will certainly be cheap, but you'll find them rather heavy for a helicopter!
This is a fascinating debate, so keep the posts coming!
Cheers
CRAN
Dave,
In response to your comments first. I am quite an admirer of your intermesher work and so will say nothing to discount this, nor will I argue the point that the first priority for a rotorcraft manufacturer is to create a good rotorcraft ~ of whatever configuration necessary.
However we must again return to the first point I made on this thread:
WHAT ARE WE TRYING TO ACHIEVE? KIT (WITH POSSIBLE PATH TO CERTIFICATION) OR ENTRY LEVEL COMMERICAL HELICOPTER?
If it’s a new commercial helicopter then you are correct, as is zeeoo, that there must be a significant improvement over the existing products else you're going nowhere fast. (Pardon the pun) Such improvements would include:
- Engine Technology
- Rotor Technology
- Structures Technology
- Avionics & Systems Technology
However if it is a kit, then a substantially improved rotorcraft can be designed over the three (practical) competitors R-22, RW 162F and Safari, simply by employing the low risk, low cost and low time-to-market strategy that I suggested. The reason I suggested this in the first place was I felt that our community would benefit from a reliable, low cost kit helicopter that they could own and maintain themselves. Remember unless one was willing to pay for such a project themselves, then you have to be able to convince would-be sponsors/customers that you will deliver TO A REALISTIC DEADLINE and high-risk approaches are a sure-fire way to scare such people off; certainly in the UK.
In response to Genghis and Zeeoo regarding the engine discussions:
G: Believe me, I also detest the Lycoming engines and their knock-offs, but when you plumb the numbers into a helicopter performance analysis then you soon see that few engines come near them. You are right about using the Rotax, but at 100hp you’re looking at a high performance one-seater or a very low performance, low payload 2-seater. I'm not convinced that there is a market for such a machine...
However, these guys are: www.dynali.com
I am a big fan of the Wilksch engines, I think they are thoroughly well engineered and based on a sound concept. Unfortunately the 120 hp unit is only good for a one-seater and the 160 hp unit not ready yet and if it was I fear any 2-seat rotorcraft based on it would be both short of payload and performance, but its certainly viable. Your comments about the Walter engines are interesting, though with a BSFC of 0.65 lb/hp-hr that engine is certainly not 'contemporary technology', an aero-engine of that size should easily achieve 0.45 lb/hp-hr with today’s technology!
Zeeoo, those Opel-GM 1.5l diesels will certainly be cheap, but you'll find them rather heavy for a helicopter!
This is a fascinating debate, so keep the posts coming!
Cheers
CRAN
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Cran,
check this one, http://www.dragonfly.co.nz/
it has been on the market for about 10 years.. never heard a bad comment.
Yes, dieselis are pretty heavy, I'm not going for that, actually, I didn't take any decision, I would trust HIRTH F30 or H30 engines, but they seem to have serious problems like plug spitting and a peaky power response, but they are cheap and powerfull.
Maybe some improvements could be fine.
I actually investigate in fitting a suzuki 750 bandit.
Yes, I go for a one seat gyrocopter. Building commencing in Jan 2005.
Dave, look at the dragonfly rotor and tell me it doesn't look like something you saw.. does it seem complicated ?
Thank you.
check this one, http://www.dragonfly.co.nz/
it has been on the market for about 10 years.. never heard a bad comment.
Yes, dieselis are pretty heavy, I'm not going for that, actually, I didn't take any decision, I would trust HIRTH F30 or H30 engines, but they seem to have serious problems like plug spitting and a peaky power response, but they are cheap and powerfull.
Maybe some improvements could be fine.
I actually investigate in fitting a suzuki 750 bandit.
Yes, I go for a one seat gyrocopter. Building commencing in Jan 2005.
Dave, look at the dragonfly rotor and tell me it doesn't look like something you saw.. does it seem complicated ?
Thank you.
Why not a turbine?
Cran,
What's wrong with the reconfigured Generator turbines like the Solar T62? My understanding, which may well be wide of the mark, is that the Solar engine is 150 hp and quite light. Yes it would need a gear-box and probably some FCU work which would add to cost and weight, but haven't these engines been proven beyond doubt in their existing stationary applications? Surely they must be nudging a tweeked Lycoming in terms of cost but are way ahead in terms of technological advancement and probably power to weight ratio.
In terms of marketing a 'kit', I think it would be more attractive if turbine powered. As one of a very small band of kit helicopter owners, and flyers, who has experienced 'kit' engine unreliability first-hand, (on several occasions!), I think the turbine is the way to go.
J
What's wrong with the reconfigured Generator turbines like the Solar T62? My understanding, which may well be wide of the mark, is that the Solar engine is 150 hp and quite light. Yes it would need a gear-box and probably some FCU work which would add to cost and weight, but haven't these engines been proven beyond doubt in their existing stationary applications? Surely they must be nudging a tweeked Lycoming in terms of cost but are way ahead in terms of technological advancement and probably power to weight ratio.
In terms of marketing a 'kit', I think it would be more attractive if turbine powered. As one of a very small band of kit helicopter owners, and flyers, who has experienced 'kit' engine unreliability first-hand, (on several occasions!), I think the turbine is the way to go.
J
This got me thinking, taking a baseline as a Continental I0-360 (since I happened to have the data to hand) that is a 6 cylinder air cooled 4-stroke, weighing about 148kg installed and generating a maximum of about 210 hp (according to my data book).
The first radical question I asked myself, is what about a twin - I know it's more complex, but it's worth asking the question at-least. So a 912s generating 100 hp weighs roughly 65.5kg installed. That's 131kg for two - or in other words two of these, plus an appropriate gearbox is not going to be all that different to a Continental in terms of installed mass. However, here's a bit of a clincher - they cost about £7k each, so that's £14k for a pair of zero-lifed engines, let's say £20-25k once you've sorted out mounts, fuel system and gearbox. Round numbers, that's the same as the cost of reconditions IO-360, before you add in the gearbox cost; so it might just offer a bit of a saving.
However, the ideal would be a turbine with similar power to the Lycontinental I'd venture. Interestingly the same data book threw up http://www.sea-plane.com/product_details_turboprop.htm ; which according to the data book generates 230hp, masses about 60kg, and will cost around £25k again. Notwithstanding that I know nothing about it, and am naturally reluctant to ever suggest wrapping a new airframe around a new engine - if it were proven, it might be a nice powerplant to wrap your shiny new 2-seat helicopter around.
So the bottom line seems to be you are likely to be spending about £25k on a powerplant regardless - and massing around 150kg for a piston engine, or maybe 90kg less for a turbine?
G
The first radical question I asked myself, is what about a twin - I know it's more complex, but it's worth asking the question at-least. So a 912s generating 100 hp weighs roughly 65.5kg installed. That's 131kg for two - or in other words two of these, plus an appropriate gearbox is not going to be all that different to a Continental in terms of installed mass. However, here's a bit of a clincher - they cost about £7k each, so that's £14k for a pair of zero-lifed engines, let's say £20-25k once you've sorted out mounts, fuel system and gearbox. Round numbers, that's the same as the cost of reconditions IO-360, before you add in the gearbox cost; so it might just offer a bit of a saving.
However, the ideal would be a turbine with similar power to the Lycontinental I'd venture. Interestingly the same data book threw up http://www.sea-plane.com/product_details_turboprop.htm ; which according to the data book generates 230hp, masses about 60kg, and will cost around £25k again. Notwithstanding that I know nothing about it, and am naturally reluctant to ever suggest wrapping a new airframe around a new engine - if it were proven, it might be a nice powerplant to wrap your shiny new 2-seat helicopter around.
So the bottom line seems to be you are likely to be spending about £25k on a powerplant regardless - and massing around 150kg for a piston engine, or maybe 90kg less for a turbine?
G
Join Date: Oct 2004
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G and jelly,
an APU sounds fine in terms of performance and reliability. Turbomeca has several small models.
But some question :
- what about the maintenance bill , do you know a turbomeca or allison workshop near your home ?
- replacing plugs or some minor parts on a piston engine can be done by quite everyone, if accepted by the manual. What about a turbine?
If you target an untralight 2 seat with a turbine, you target people with some financial means, not the "poor" tubes-n-bolts builder. Doing so, you will chalenge used helicopters and the choice between used but proven swheitzer or h300 will not be that easy.
for info : I had the occasion 10 years ago to buy a used alouette II (5 seat) from a sale (of 10 items) from french ALAT, they were all zero life but sold with the complete spare parts set for about 120.000 F, about 20.000 euros each. Alas I didnt have enough money at this time, not to buy it but to repair it.
BTW, a lot of ag sprayers dont like turbine aircrafts for that job.
If you plan to market it, maybe the very first job is to list existing machines, prices, sales, + and - and to try to do something covering BETTER the targeted market.
thanks
an APU sounds fine in terms of performance and reliability. Turbomeca has several small models.
But some question :
- what about the maintenance bill , do you know a turbomeca or allison workshop near your home ?
- replacing plugs or some minor parts on a piston engine can be done by quite everyone, if accepted by the manual. What about a turbine?
If you target an untralight 2 seat with a turbine, you target people with some financial means, not the "poor" tubes-n-bolts builder. Doing so, you will chalenge used helicopters and the choice between used but proven swheitzer or h300 will not be that easy.
for info : I had the occasion 10 years ago to buy a used alouette II (5 seat) from a sale (of 10 items) from french ALAT, they were all zero life but sold with the complete spare parts set for about 120.000 F, about 20.000 euros each. Alas I didnt have enough money at this time, not to buy it but to repair it.
BTW, a lot of ag sprayers dont like turbine aircrafts for that job.
If you plan to market it, maybe the very first job is to list existing machines, prices, sales, + and - and to try to do something covering BETTER the targeted market.
thanks