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Airbus H160 helicopter

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Airbus H160 helicopter

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Old 4th Mar 2015, 07:25
  #21 (permalink)  

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Very nice looking piece of equipment; it's even got "VIP skids" for ground taxying!
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Old 4th Mar 2015, 07:26
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They might need to rebrand the company since they're not going to be only making buses anymore !
Perhaps they could change the name to something like



Oh wait, they just did ...
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Old 4th Mar 2015, 07:32
  #23 (permalink)  

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Instead, the size of the landing gear doesn't impress me so much..
At least it can ground taxi, unlike the so-called "VIP" EC135 which makes a terrible scraping noise....
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Old 4th Mar 2015, 12:49
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It takes more than good looks to "kill the139", let's call the H-160 (sounds like a Renault product, just like the vent registers on its dashboard) a medium light twin with decent (paper) performance.
Oh, and probably a "smooth ride and an airy interior".
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Old 4th Mar 2015, 14:21
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Question - is 3dB really worth what those blades are going to cost on ship?

I can't imagine the potential fatigue issues they might end up facing in long term operation.
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Old 5th Mar 2015, 08:32
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Learn your dB scales.

It's a reduction of half.
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Old 5th Mar 2015, 16:27
  #27 (permalink)  
 
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Learn what a decibel is.

3dB does not equate to a subjective "halving" of noise.

3 dB increase is, by definition, a doubling of power in watts

3 dB = twice the power (calculated)
6 dB = twice the amplitude (Voltage respective sound pressure - mostly measured)
10 dB = twice the perceived volume (psychoacoustics)

Nobody in their right mind would characterize a doubling of power as a doubling of volume.
In any case, the difference is noticeable, but certainly not half.

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Old 6th Mar 2015, 15:02
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Unless mistaken, logarithmic dB scale can be applied to any physical quantity. If talking about noise, it is about sound pressure levels in Pa.

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Old 6th Mar 2015, 17:49
  #29 (permalink)  
 
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Correct, and doubling of dB(SPL) does not equate to a doubling of psychoacoustic volume.

If you have a decently high end audio receiver at home, let me know if going from -25dB to -22dB on the volume makes you jump out of your sofa for being "twice as loud"!

Axiom AudioFile Newsletter

Now for the really amazing part: although it seems that doubling the amplifier power in watts would also double the loudness, disappointingly it only increases loudness by 3 dB, a change in volume most of us perceive as “slightly louder.” That’s why going from an amplifier of 75 watts output to one of 150 watts output only increases the actual acoustic output a bit—again by 3 dB. To make sounds subjectively “twice as loud”—an increase of 10 dB—requires ten times as much power from the amplifier.
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Old 6th Mar 2015, 19:32
  #30 (permalink)  
 
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Purely academic, but:
based on press data: - 3 dB noise, which means - 3 dB SPL.

In an audio system a 3 dB SPL change would require about 6 dB accoustic power change (x4) and would give about 50% volume change (subjective).

As we are not talking about music (20 Hz - 20 kHz spectrum) but about noise of limited spectrum and our hearing subjective reaction will depend on that noise spectrum, time duration of peaks, etc... the final answer is I don't know.
Probably around 50% volume reduction (but see remark above).

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Old 6th Mar 2015, 20:26
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In an audio system a 3 dB SPL change would require about 6 dB accoustic power change (x4) and would give about 50% volume change (subjective).


3dB SPL =/= 50% subjective volume
increases loudness by 3 dB, a change in volume most of us perceive as “slightly louder.”
10db SPL = 50% subjective volume
To make sounds subjectively “twice as loud”—an increase of 10 dB—requires ten times as much power

To achieve the subjective "50% volume change", it's universally agreed in industry that the average noise (not necessarily music frequency range) dB reduction would need to be 10dB SPL.

The blue edge blade design claims a reduction of 3dB SPL.

The blue edge blade does not reduce perceived blade noise volume by 50%.

Q.E.D.

Last edited by SansAnhedral; 6th Mar 2015 at 20:38.
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Old 6th Mar 2015, 21:00
  #32 (permalink)  
 
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Lets see now -

What the EC155 really should have been instead of cobbled 365 parts?

Similar concept with a new brush?

Should be fast and quiet if improved in those respects as the 155 certainly is.

When will you see it certified? I would guess about 3-4 years at best.

Clean sheet?
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Old 6th Mar 2015, 21:18
  #33 (permalink)  
 
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Q.E.D
I'm affraid not. From the begining, You are mixig things.

A 10 dB of accoustic power change gives effectively x2 volume change but also a little bit over 3x SPL change (noise level, we are talking about).
Please try to make the difference between accoustic power, SPL (nosie level) and loudness (volume).
From AH press release
Airbus Helicopters
we are talking about
which reduce exterior noise levels by 50 percent (3 dB)
and not 3 dB power reduction which is not the same.

I also made a mistake. It should be approx. 23% volume. The value of 50% volume change would be for 6 dB of noise reduction. Not enough sleep I presume

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Old 7th Mar 2015, 08:41
  #34 (permalink)  
 
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on a new aircraft why is the 30second oei (blue line on fli) so much less than mcp? The pic shows the radalt and bar alt to be below 2000ft and only +9c. Acceptable risk in an old aircraft, but for me in a new twin I want to be able to cruise at close to mcp and not have to immediately be lowering collective to save rpm if a power unit quits.

Also why is the TOP range quite small with an almost equal transient range?
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Old 8th Mar 2015, 18:37
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It is a static display model... ;-)

I know nothing about this aircraft but think the demo display is showing the OEI mode of the FLI. If previous aircraft are anything to go by the 30s OEI rating would be the solid red line on top of the amber band and not the blue line. By definition MCP OEI must be less than the 30s OEI rating.

Also I would expect the aircraft in case of an engine failure to automatically manage the power for you (even if this wasn't the case I think an engine failure in the cruise is a bit of a non event) so I don't really see much risk there.

But then again I could be completely wrong! ;-)
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Old 29th May 2015, 21:44
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First ground run :

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Old 14th Jun 2015, 19:26
  #37 (permalink)  
 
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First flight:



I/C
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Old 14th Jun 2015, 20:22
  #38 (permalink)  

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A rather unfortunate combination of letters on that registration...
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Old 14th Jun 2015, 21:12
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Erm, has anybody else noticed the differences between the mock-ups and the actual aircraft (particularly around the cowlings)?




...and...


Sleek and aerodynamic seems to have turned into bulky and awkward.
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Old 14th Jun 2015, 21:40
  #40 (permalink)  
 
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And top heavy to taxy with the narrow track
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