Sikorsky S-65 projects

[hesham]

Yes TinWing,

The Sikorski S-65 as 80-seat compound helicopter project.

Source:

http://www.flightglobal.com/pdfarchive/view/1967/1967%20-%200924.html

 

[hesham]

Thank you my dear Jemiba,

and the Sikorsky S-65 in 1970.

http://www.flightglobal.com/PDFArchive/View/1969/1969%20-%201479.html?search=Sikorsky%20aircraft%20project

 

[overscan (PaulMM)]

S-65-200 and S-65-300 compound helicopters.

Developed from CH-53. S-65 was a straighforward civil development of CH-53 with fuselage extension. S-65-200 has tractor propellers and would carry up to 86 passengers at 265mph. MTOW about 63,600lb. S-65-300 is a military derivative of the -200.


Source:

Flying Review International August 1970

 

[Jemiba]

Three-engined, pressurized civil version of the S-65 :
(from Aviation Week 9/1965)

 

[Antonio]

Another S-65 pic

http://www.flightglobal.com/PDFArchive/View/1964/1964%20-%202538.html

 

[Orionblamblam]

I've got a number of S-65 illustrations and drawings in paper, but this is the only one I seem to have scanned so far.

 

[Triton]

Artist's impression of Sikorsky S-65-200 convertiplane with a 79-foot helicopter rotor, small wings. and two turboprop engines. Seating capacity is 86 passengers.

Source: Kocivar, Ben."Your STOL-Bus Is Coming" Popular Science May 1970

 

[hesham]

thank you my dear Jemiba,

and the Sikorsky S-65 in 1970.
http://www.flightglobal.com/PDFArchive/View/1969/1969%20-%201479.html?search=Sikorsky%20aircraft%20project

Very strange,

in Flightglobal,they spoke about the Sikorsky S-65-200 as S-200,
and may be that means DS-200 design .

http://www.flightglobal.com/pdfarchive/view/1971/1971%20-%200921.html
http://www.flightglobal.com/pdfarchive/view/1971/1971%20-%200922.html

 

[Stargazer2006]

in Flightglobal,they spoke about the Sikorsky S-65-200 as S-200,
and may be that means DS-200 design .

No. There were several iterations on the basic S-65 design, the S-65-200 civilian transport and the S-65-300 military transport, notably (both vee-tailed, see pictures below). Nothing to do with "DS-" numbers. Third picture shows an earlier configuration with single fin. Last attachment shows the initial S-65 design (the produced aircraft was the S-65A).

 

[Caravellarella]

in Flightglobal,they spoke about the Sikorsky S-65-200 as S-200,
and may be that means DS-200 design .

No. There were several iterations on the basic S-65 design, the S-65-200 civilian transport and the S-65-300 military transport, notably (both vee-tailed, see pictures below). Nothing to do with "DS-" numbers. Third picture shows an earlier configuration with single fin. Last attachment shows the initial S-65 design (the produced aircraft was the S-65A).

Dear Stéphane, here is a piece in French announcing development of the Sikorsky S-65 compound helicopter (which remained a "project"). It comes from the 1st February 1969 issue of Aviation Magazine International......

Best, Terry (Caravellarella)

 

[Caravellarella]

Dear Boys and Girls, here are pictures with a caption in French of the Sikorsky S-65 helicopter "project" and a Sikorsky co-axial rigid-rotor compound helicopter "project" (together with Lockheed CARR Retractoplane "project"). The pictures come from a larger article about the future of VTOL flight.....

The picture comes from the 15th May 1969 issue of Aviation Magazine International......

Terry (Caravellarella)

 

[Stargazer2006]

Careful! The caption doesn't call the first project an "S-65". It says: "Left to right, a 20-ton Sikorsky project with two contra-rotative rotors and two tractor propellers, derived from the S-65; then another, more ambitious one, using two twin-flux jets and weighing 50 tons. Meanwhile, Lockheed (right) offer designs with rotors that retract inside the fuselage, with short wings and two turboprops in typical fashion; this is of these, which was revealed very recently."

 

[Caravellarella]

Careful! The caption doesn't call the first project an "S-65". It says: "Left to right, a 20-ton Sikorsky project with two contra-rotative rotors and two tractor propellers, derived from the S-65; then another, more ambitious one, using two twin-flux jets and weighing 50 tons. Meanwhile, Lockheed (right) offer designs with rotors that retract inside the fuselage, with short wings and two turboprops in typical fashion; this is of these, which was revealed very recently."

Gosh, my translation skills are truly appalling

 

[hesham]

Hi,


I find this DTIC report about Sikorsky DS-507 rotor design for S-65-300,


http://www.dtic.mil/dtic/tr/fulltext/u2/740911.pdf

 

[Mark Nankivil]

Greetings All -

[Found on eBay]

Enjoy the Day! Mark

 

[hesham]

Here is the Sikorsky S-65-40 and S-65-200 projects;


http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19720014365_1972014365.pdf
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19740021980_1974021980.pdf

 

[yasotay]

I wonder why Sikorsky never considered (or did they?) differetial thrust on the props/fans for anti-torque. Of course it is easy to wonder now that Eurocopter has demonstrated this as a viable technique.
Anyone want to venture a guess?

 

[Sundog]

I wonder why Sikorsky never considered (or did they?) differetial thrust on the props/fans for anti-torque. Of course it is easy to wonder now that Eurocopter has demonstrated this as a viable technique.
Anyone want to venture a guess?

Because the flight control computers and software of the era weren't up to the task? Or if there were systems up to the task, for the time period, they may have been weight and cost prohibitive; i.e.-too much money to make the product viable.

 

[Stargazer2006]

I find this DTIC report about Sikorsky DS-507 rotor design for S-65-300,
http://www.dtic.mil/dtic/tr/fulltext/u2/740911.pdf

Better quality scans of the S-65-300 compound project can be found in this document:

• VARIABLE DIAMETER ROTOR STUDY (Sikorsky, January 1972)

 

[yasotay]

I wonder why Sikorsky never considered (or did they?) differetial thrust on the props/fans for anti-torque. Of course it is easy to wonder now that Eurocopter has demonstrated this as a viable technique.
Anyone want to venture a guess?

Because the flight control computers and software of the era weren't up to the task? Or if there were systems up to the task, for the time period, they may have been weight and cost prohibitive; i.e.-too much money to make the product viable.

That would be my guess as well, but I consider that the state of the art of turbo-prop pitch control was fairly advanced at the time. I have to wonder if the weight penalty for the tail rotor was any less than the analouge controls required for the pitch control on the props.

 

[Stargazer2006]

A COMPOUND HELICOPTER (shown here in artist's conception) is under study by Sikorsky Aircraft, Stratford, Conn. The proposed aircraft, basically a Sikorsky S-65, would carry 80 passengers at cruising speeds up to 223 miles an hour over distances of about 150 miles at direct operating costs per available seat mile of 3 to 31/2 cents. The aircraft would use components of a growth version of the S-64 Skycrane, including a rotor 79 feet in diameter.
Power would be provided by three G.E. T-64 engines. Lift at cruising speed would be provided almost entirely by fixed wings, and thrust by the two turboprop engines mounted on the wings.

Source: Sikorsky promotional photo

 

[Stargazer2006]

Sikorsky Aircraft's proposed S-65 compound helicopter could carry 86 passengers at cruising speeds of 265 miles an hour on short haul inter-city routes. Direct operating costs would "be 2.5 cents per available seat mile.

Source: Sikorsky promotional photo, released January 8, 1969

 

[Stargazer2006]

By adding wings and propellers, Sikorsky's S-65 commercial airliner can be made into a compound aircraft, which takes off and lands vertically like a helicopter but achieves fast forward speeds like an airplane. Being able to land near city centers, this aircraft, called the S-65-200 compound, will reduce overall trip time for travelers by eliminating the necessity for trips to and from the airport. This aircraft will be able to carry 86 passengers in airliner comfort at a cruise speed of 265 miles (426 kilometers) an hour.

Source: Sikorsky promotional photos

 

[Stargazer2006]

Artist's conceptions show proposed Sikorsky S-65-300 compound helicopter in two Air Force mission configurations. Top illustration depicts the aircraft as a light intra-theater transport (LIT). Bottom illustration depicts the aircraft in the advanced rescue system (ARS) role.

Source: Sikorsky promotional photos, released September 22, 1969

 

[Stargazer2006]

Artist's rendering shows how Sikorsky S-65 would look as a commercial airliner.

Source: Sikorsky promotional photo

 

[Stargazer2006]

Large heliports, such as the one depicted here, with access to several forms of surface transportation could handle most of the short-haul traffic that is presently congesting major airports. Large compound helicopters, such as the Sikorsky S-65-200, would take off and land vertically but with the addition of stubby wings and propellers would have fast cruise speeds.

Source: Sikorsky promotional photo, no date

 

[hesham]

Hi,


not a project,but early Model for S-65,page 60;


http://books.google.com.au/books?id=Kunkz7gc0akC&pg=PA124&dq=flying+magazine+1962&hl=en&sa=X&ei=wmwVVM_BGse-PMy0gZAE&ved=0CDAQ6AEwAzgK#v=onepage&q=flying%20magazine%201962&f=false

 

[Stargazer2006]

not a project,but early Model for S-65,page 60

By simply cutting the URL after the page number, you provide a direct link to the page.
In this case it was "PA124" for page 124 (because you had arrived on that page initially) but by replacing "124" by "60" I reached your image right away:

http://books.google.com.au/books?id=Kunkz7gc0akC&pg=PA60

 

[hesham]

OK my dear Skyblazer.

 

[hesham]

Hi,


here is a Sikorsky CH-53E as airliner version;


http://www.dtic.mil/dtic/tr/fulltext/u2/a051589.pdf

 

[hesham]

Hi,


here is a Sikorsky S-65 with emergency flotation system study;


http://www.dtic.mil/dtic/tr/fulltext/u2/a101640.pdf

 

[hesham]

And;

 

[Stargazer2006]

here is a Sikorsky CH-53E as airliner version

Interesting. I've always counted it a great loss that the S-65 airframe be not developed into civilian derivatives.

Perhaps this has to do with the military having a say on not sharing the technology of such sensitive machines... Then again, maybe not, since originally the S-65 was little more than a "full" version of the S-64 Skycrane, wasn't it??

 

[hesham]

Hi,


initial design for Sikorsky S-65 or CH-53.


http://www.dtic.mil/dtic/tr/fulltext/u2/a584392.pdf

 

[Abraham Gubler]

Interesting. I've always counted it a great loss that the S-65 airframe be not developed into civilian derivatives.

Perhaps this has to do with the military having a say on not sharing the technology of such sensitive machines... Then again, maybe not, since originally the S-65 was little more than a "full" version of the S-64 Skycrane, wasn't it??

Paying passengers tend to not like being dripped on all the time by transmission oil. The old saying goes if the CH-56 isn't leaking into the cabin then it isn't safe to fly in.

 

[yasotay]

Interesting. I've always counted it a great loss that the S-65 airframe be not developed into civilian derivatives.

Perhaps this has to do with the military having a say on not sharing the technology of such sensitive machines... Then again, maybe not, since originally the S-65 was little more than a "full" version of the S-64 Skycrane, wasn't it??

Paying passengers tend to not like being dripped on all the time by transmission oil. The old saying goes if the CH-56 isn't leaking into the cabin then it isn't safe to fly in.

Very true. They used to say the same about the CH-47 by the way. I also think that the substanical noise and vibration environment would not have been well met by the paying public. There would have had to have been a significant effort (as in money) to reduce both to "civil" levels.

 

[joncarrfarrelly]

The more likely explanation is that the civil versions of the S-61 (non-amphibious L, and amphibious N) were not exactly
a screaming success. Sikorsky and various operators gave it the old college try, but the market simply wasn't there.

 

[Abraham Gubler]

Sikorsky and various operators gave it the old college try, but the market simply wasn't there.

True and the only commercially viable market for passenger helos is strongly associated with the oil and gas industry. And CH-47s and CH-56s are apparently too big for their needs.


Be interesting if anyone tries to commercialise the V-22. Downtown heliport to downtown heliport at higher speeds and ranges. Plenty of 1950, 60s and 70s era studies saying such a transport option would be viable. Just needs someone to build it and see if they will come.

 

[frank]

And of course the CH-56 is a transport version of the AH-56 Cheyenne, right?

 

[TomS]

Be interesting if anyone tries to commercialise the V-22. Downtown heliport to downtown heliport at higher speeds and ranges. Plenty of 1950, 60s and 70s era studies saying such a transport option would be viable. Just needs someone to build it and see if they will come.

There hasn't been much interest. There is the AW609 civil toltrotor, which is a good deal smaller. Orders for that have been shrinking as development gets dragged out.

I suspect cell phones and wireless data access are major killers for downtown-to-downtown air travel -- time spent in a limo to and from a close-in airport to catch a shuttle flight is no longer totally dead time like it once was, so fewer people are willing to pay the premium.