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-   -   Lets make a helicopter (https://www.pprune.org/rotorheads/152384-lets-make-helicopter.html)

Dave_Jackson 23rd November 2004 19:47

OK forget the rotor :{ ~ for a moment :D .


Weight:

Reducing the weight of the craft's components allows for more of the other goodies (safety, reliability, payload etc.) to be put in. The following is an excerpt from an article in this mornings paper entitled 'Airbus aims to trump Boeing'.

" the company [Boeing] plans to build the airplane [7E7] largely out of carbon-fiber composite panels, which are lighter and more resilient than aluminum, the material from which almost all planes are made today."

This large and ever increasing consumption of carbon will result in a continuing decrease of its cost. If the cost of the first prototype is a serious problem, one might consider the use of timed-out carbon prepreg, or fiberglass with an extra layer or two.

zeeoo 23rd November 2004 20:17

Dave,
I would agree more on the "timed-out" thing.
Often, things that were high-tech 2 years ago are considered as obsolete now, but never forget they were high-tech only 2 years ago (ex : computers). If the solutions get more and more sophisticated for marketing reasons, it doesnt mean that you must follow the rythm.. Do I express my self right ?
In other words : if Excell or Word ran fine on a 3 years old computer, you don't need faster to run them, maybe ou could enjoy smaller.

thanks

PS : Airbus are not yet full-carbon, and we, you and all here are not yet Airbus R&D bureau, alas :}

jimgriff 23rd November 2004 21:24

Has it occured to anyone that a mega bucks company wishing to plug a hole in the market has just had all it's market research done F.O.C?

CRAN 23rd November 2004 21:44

If it means 'big bucks company X' gets something to the market in the near future that fulfils the requirements that we have collectively identified then surely the thread has benefited the Rotorhead’s community.

Chances are though, they will disregard the thread as completely unverifiable information, assume that any 'small project' will fail to get anything to market and so do nothing. In that case then others may choose to benefit from the information generated by our group.

In the vast majority of cases the internet is only a starting point, in isolation it does not represent a reliable source of information as it is not subject to peer review or quality control.

CRAN
:cool:

RDRickster 23rd November 2004 21:51

Hole in the market? What hole?
 
Besides, this is a discussion in theory. There isn't any market research presented on this thread. I get a chuckle when I see young entrpeneurs identify "market research" as browsing the web for a few statistics here and there... mostly from unproven sources.

It takes a lot of work to establish a business, and the folks that start out will usually make less than minimum wage when compared to the enormous effort required to get something off the ground (pun intended). Successful business owners are the ones that get to do something they really love, or build on an idea that is simple and reproducable. I'd rather go with the "something you love" concept.

It will be interesting and fun to see these dreams and thought put into action.

zeeoo 23rd November 2004 22:20

RD, You go first ? ;)

Dave_Jackson 24th November 2004 19:42

Evolution or Revolution
 
OK! Due to popular demand, it's back to the rotor. http://www.unicopter.com/7up.gif[list=1][*]Nature's creatures are laterally symmetrical. (Trivia ~ Even facial symmetry is advantageous when attracting a mate.) [*]Man's improvements are founded in nature.[*]Vehicles, excluding abnormalities such as motorcycle sidecars and tail rotor helicopters, have lateral symmetry.[/list=1]
The non-rotor related crash of the 3-blade intermeshing Kellett helicopter and the death of the test pilot put an end to Kellett's intent to build a stronger rotor. Since then, two generations of stronger and lighter materials have become available for the production of rotors with greater rigidity.
  • Is it not time to take the helicopter up a generation or two?
  • Is it not time to reconnect with the ingenuity of Nature and the aspirations of Flettner and Kellett?
  • Is PPRuNe not the place to pull ahead of the crowd? :ok:
  • Last and least ~ Is this posting a little too brash to be a 'letter to the editor' of AHS's Vertiflite? :O

zeeoo 24th November 2004 21:38

Dave I am ok, excepted with the symetrical thing : see mapple tree fruit.. a perfection in dissimetry.

To progress : ok !
Let's search impromements in the way to GET LIFT instead of improving an old idea such as a rotor :D, what a complicated and dangerous device.. ducted fans maybe? High-pressure jets ?
check kestrel aerospace.. maybe a clue.
cheers

Dave_Jackson 16th December 2004 20:12

Just a note or two.
 
Marketability:

The following web page has information on the U.S. Sport Pilot / Light Sport Aircraft Category . Helicopters are not included at present, but there is the opening for their inclusion in the future. " Helicopters - no value, helicopters are too complex to be allowed under this first issue of SP/LSA rules. "

Those who are considering the production of a very light rotorcraft for a broad market may wish to consider these rules in conjunction with those of JAR-VLR and BCAR-VLH.


Weight:

It appears that the maximum weight for SP/LSA rotorcraft has been increased to 1320 lbs (600 kg) gross, from the previously mentioned 1232 lbs (560 kg) gross. This GW is now the same as JAR-VLR.

One modern 2-seat helicopter that is manufactured out of current materials is the Ultrasport 496. Its empty weight is 575 lbs., its useful load is 605 lbs., and its gross weight is 1,180 lbs (536 kg). This proves that new small helicopters can be (and should be) produced with an empty weight to payload ratio that is very close to 50/50.

The current Robinson R-22 Beta II has a payload of 515 lbs and a GW of 1,370 lbs.. The use of modern materials should allow this payload to be maintained or slightly increased, while the GW is reduced to below the JAR-VLR and SP/LSA ceilings of 1320 lbs (600 kg)


Dave


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