First flight EC175

[Pete]

Pete -

Can't go into detail, but 'covers' will not be required for the floats & rafts. As you mention, on the Super Puma family these devices are enclosed in the sponson, but a different design approach is used on the EC175. Trust me, they're there!

Okay i trust you ( for the time being)

The other question i have is: Why are the exhaust positioned in this way, it seems to be pretty hot for the helideck crew on the offshore platform to reach te luggage compartment?

Regards Pete

[A Legal Alien]

The exhaust design is dictated by the PT6, which is a hot-drive turboshaft. Since the engine has to be installed 'backwards' in order to keep the output drive need the main gearbox (a 'problem' common to the PT6 turboprop), the engine's exhaust is also farther forward than on helicopters powered by 'conventional' cold-drive layout engines, such as the UH-60/T700. On the AW139, this problem was solved by the use of a labyrinthine exhaust system. The EC175 layout is simpler.

Your helideck question is a good one, but the efflux will not impinge on ground crew (have a look at the photos from today's event and you'll see how the gas path interacts with the fuselage and rotor). Should you be interested, the luggage doors are upward opening, providing protection from the elements for ground handlers.

I can understand you questioning the credentials of a newbie. Unfortunately there's only so much I can share. You'll see more detail appear on the program over the next couple of years.

[Pete]

I can understand you questioning the credentials of a newbie. Unfortunately there's only so much I can share. You'll see more detail appear on the program over the next couple of years.

A Legal Alien,

Once again thanks for your explanation. My questions had nothing to do with the credentials of a newbie. I figured you took the effort to sign up for this wonderfull forum to invite us to raise questions/remarks about the design, so you could put us at ease. (imho that makes you a Eurocopter insider.)

I tried to take advantage of your knowledge.

Regards Pete

[topgun1984]

@A Legal Alien

One of my things that i don't like about the model is that it hasn't got a fanrotor. (or is it because it almost looks like a 155 then). Because IMHO the sound produced would be less then in a fanrotor configuration. If i look at it it screams that it was designed and someone forgot to place a tail rotor on it. It almost looks like one of the UH-60 wich is also a very noisey bird. Why did eurocopter did this you think?

I do believe that it this chopper could function quite well but i do am concerned about the heat coming from those exhausts. Like you said this is propelled by PT-6 turboprops. Why not a normal configuration?


Grtz,

TG1984

[Hans]

Apparently the actual first flight already was on 4 December (see http://www.ainonline.com/news/single-ne ... st-flight/" onclick="window.open(this.href);return false; and some of the dates with the images I mentioned in the first post).
Just wondering why the official first flight was only two weeks later

Regards,

Hans

[topgun1984]

Apparently the actual first flight already was on 4 December (see http://www.ainonline.com/news/single-ne ... st-flight/" onclick="window.open(this.href);return false; and some of the dates with the images I mentioned in the first post).
Just wondering why the official first flight was only two weeks later

Regards,

Hans

Somtime you wonder to much hahaha LOL

[A Legal Alien]

Pete - Happy to assist.

topgun1984 - The Fenestron has clear advantages vs. conventional tail rotors for small and intermediate sized helicopters, but it encounters a sizing issue once you get above a certain weight class (you may have seen the photo of Puma SA330Z with the oversized Fenestron). The EC175 sits on the edge of the 'usable' size range for Fenestrons, but in the end the decision was made to make use of experience gained with the Tiger's 3-blade tail rotor, which is surprisingly quiet. Also, sorry if I confused you with the PT6 turboprop reference. The engines are turboshafts (PT6C-67E), but they share the 'back to front' installation idiosyncrasy of the PT6A prop (which, with a few exceptions (e.g. the P180 Avanti), requires front drive). This is why the exhaust is so far forward. If you look into the AW139 program, you'll see that the engineers did a nice job in ducting the exhaust to the rear of the engine nacelle, but unfortunately this approach leads to issues with regards to power losses, heating and weight.

Hans - The EC175 proudly joins the ranks of the A-12, U-2 and F-16 in flying before its official date! The practical reason for doing this is, of course, to avoid any embarrassment in front of the VIPs, and it's a fairly common practice (other examples including the Rafale, ATR600, ERJ145, Dhruv, Ka-60 and Ka-226).