Lack of intercoms in Boeing/Airbus aircraft??

[daysleeper2621]

I've been noticing in some threads where pilots are discussing what type of headset they prefer in their aircraft and I keep seeing how 737's and some Airbus aircraft don't have intercom systems for the crew in the cockpit to be able to talk to one another. Is this true for all large aircraft? And if so, why in the world does Boeing and Airbus build multi-million dollar aircraft without a simple intercom when the 172's I fly come with an intercom as standard as well as push to talk buttons for both sides? And my last question, what's the use of headsets in large aircraft if all they do is block out noise? Why not just buy the new Bose noise cancelling headphones that can be used to listen to cd players as well as make it more quiet for the user?

 

[Jedi_Cheese]

If I remember correctly from when I toured a SW aircraft for a class, you don't have 172 type headsets. You have a headset like a telemarketer would have (the one earphone and a mic).

They don't have 172 type headsets because there isn't as much noise to filter out. The engines are several hundred feet from the pilots and the cabin is sealed so less of the noise gets in.

 

[flx757]

On all 737s I have flown (and the ones here at Alaska), as well as the MD-80, 757 and 717 (I can't remember about the A-320, but I can't imagine that it doesn't); they all have a flight interphone over which the pilots can communicate.

On the MD-80 for example, you can either select a "hot mic" type interphone, or select the "flight interphone" position on the audio select panel, then transmit over the interphone via the push to talk button either on the audio panel or the yoke.

 

[U-I pilot]

The engines are several hundred feet from the pilots

Is this a fish story....? I havent seen too many planes where this is the case

 

[flx757]

Is this a fish story....? I havent seen too many planes where this is the case

More "fun facts". The MD-80, with tail mounted engines, is 147 feet, 10 inches from the tip of the nose to the end of the tail. So, I'd guess the engines are just over 100' from the pilots. Certainly not "several hundred". Keep in mind, this is on a relatively long aircraft with tail mounted engines. I think "several hundred" feet might be "stretching" it a bit...

 

[daysleeper2621]

If this is the case that there isn't as much noise in the cockpits of the 737, MD-80's, etc., then why are pilots for the majors on another thread discussing which type of ANR headset is the best for their jobs? Some even talk about how they have to leave one earcup off to hear the captain speaking. This would make no sense why they would have to take an earcup off to hear the other officer in the cabin if both can speak to each other through their headphones. Check this thread out:

http://forums.flightinfo.com/showthread.php?t=35851

 

[English]

I fly the 737-200. It is LOUD, mainly wind noise, but still loud. I cannot hear the captains that speak in a normal or subdued voice unless I keep my left ear uncovered. Standard issue in our aircraft is the Telex 750. We do not use an intercom.

The C172s that come with an intercom as standard and PTT switches were probably built in the early 80s or more recently. These aircraft are older than that.

There is a flight interphone, but you have to press a button each time you speak to use it, so no one (at least at my company) bothers.

 

[flx757]

FWIW, the 737 (like the 727) is fairly noisy (wind noise), especially when compared to the MD-80...or 757 for that matter, but especially the MD-80.

 

[daysleeper2621]

But just to get the facts straight, the aircraft that are being built today by Boeing and Airbus do have intercoms for the crew in the cockpit just like the intercoms I'm used to in the 172's I fly without having to press any buttons to talk to one another? Sorry for all the questions, it just struck me as very odd that a very expensive aircraft built for 2 or more pilots in the cockpit would not have any means for the crew to speak to one another except for over all the noise in the cockpit. Thanks for the answers guess.

 

[Skygod]

The A-320 is nice and quiet up front, and so for the vast majority of the time we operate 'topless' -- no headsets. Works great.

However when taxing, taking off, landing, and infact any time below 18,000 ft MSL it is an FAR that airlines use headsets with boom mikes. So we do. And with the increased workload combined with the increased noise (higher IAS and power settings) it also works well. At my company we have lightweight telex jobs supplied at each pilot station, and the system has a hot mic intercom.

In noisy planes like the ATR or EMB, used to wear 'delta charlies' (David Clark) headsets/vice clamps for noise reduction and hot mic intercom for the entire flight.

Hope this helps.