787 unsafe?

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Re: 787 unsafe?

Postby expat » Sun Oct 14, 2007 6:58 am

Nope, A320 was at mid thrust, and so was the 717. Pointing up into the air to try and fly. :P ;)



Well the A320 would have been doing exactly what the flight computers wanted it to do regardless of the what the pilot was wanting if you where in such dire straits, also if it was "trying" to fly, then it would be using more than mid thrust (and how do you know that it was mid thrust?)

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Re: 787 unsafe?

Postby Slotback » Sun Oct 14, 2007 7:34 am

You guys are familiar with FLCH, and VNAV in airliners, right? Well they all make the aircraft decend at idle power weilding a decent rate of typically 2000 feet per minute. Unless conditions dictate otherwise an Airliner usually decends on idle power untill it's relatively low.

On final, planes approach at a set speed for their current weight so the nose does not need to be pointed high. The only reason there would be a profound diferance between two aircraft is if one had slats and one doesn't, or if one came in high and the other didn't. Also, even on final, a Boeing 717 is going to be at a very low power setting, It aint called the lead sled for nothing and infact, when lightly loaded its stall speed will be under 100 knots. I recall 89knots or so with Flaps 40, though I may need to check up on that.

I'd like to know your source regarding Boeing vs Airbus climb performances.  
Where did yu hear this?

I came to that conclusion after years of reading on A.net, PPRUNE, AirlinepilotCentral, and askcaptainlim.... I'll find some links for you tomorow.
Last edited by Slotback on Sun Oct 14, 2007 7:47 am, edited 1 time in total.
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Re: 787 unsafe?

Postby Nexus » Sun Oct 14, 2007 8:28 am

Slotback,  you came to that conclusion while reading forums such as airliners.net?
A place where roughly 5% only has a real clue whats going on.  :-?

And a 717 with flaps 40 will have a quite high power setting since the flaps creates significant amount of drag.
The more flaps you have, the more drag they create ...the lift coefficient decreases while drag increases for the more amount of flap you select.
Thats why you usually dont land flaps full unless there really is a need for it. Or you are flying an airbus...  ;)
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Re: 787 unsafe?

Postby C » Sun Oct 14, 2007 8:36 am

Maybe the A320 and 717 descended on idle thrust which creates more Gs since the RoD is greater.


Either way, the ROD will have absolutely no effect on the "G" unless you retard the RoD rather ham-fistedly at the bottom of the descent (considering on most airliners high "G" is up around 1.5G) , or later, on very late finals, forget to flare (or do it too late - fortunately my only ever 4G landing was in an aeroplane built to take it)... :)
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Re: 787 unsafe?

Postby Nexus » Sun Oct 14, 2007 12:17 pm

Maybe the A320 and 717 descended on idle thrust which creates more Gs since the RoD is greater.


Either way, the ROD will have absolutely no effect on the "G" unless you retard the RoD rather ham-fistedly at the bottom of the descent (considering on most airliners high "G" is up around 1.5G) , or later, on very late finals, forget to flare (or do it too late - fortunately my only ever 4G landing was in an aeroplane built to take it)... :)


I shoul've expressed myself more clearly.  :-[
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Re: 787 unsafe?

Postby C » Sun Oct 14, 2007 12:36 pm

Maybe the A320 and 717 descended on idle thrust which creates more Gs since the RoD is greater.


Either way, the ROD will have absolutely no effect on the "G" unless you retard the RoD rather ham-fistedly at the bottom of the descent (considering on most airliners high "G" is up around 1.5G) , or later, on very late finals, forget to flare (or do it too late - fortunately my only ever 4G landing was in an aeroplane built to take it)... :)


I shoul've expressed myself more clearly.  :-[
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Re: 787 unsafe?

Postby Xyn_Air » Sun Oct 14, 2007 11:08 pm

I am just going to take a quick moment here to jump back to the original article . . . and the complaining fellow's comments (in the article) that the 787 would be dangerous in a crash:

:o Um.  Yes.  That's why we land planes at our destinations rather then just piling them into the ground in the general vicinity of where we want to go.  Duh! ::)
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Re: 787 unsafe?

Postby Slotback » Mon Oct 15, 2007 1:00 am

[quote]Slotback,
Last edited by Slotback on Mon Oct 15, 2007 1:04 am, edited 1 time in total.
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Re: 787 unsafe?

Postby an-225 » Mon Oct 15, 2007 4:32 am

Calm down Nexus, I never stated that it was fact. I simply stated that it looked like.  :-X I simply will keep my mouth shut from now on, I seem to be causing anger wherever I go.  :-? :-X
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Re: 787 unsafe?

Postby Nexus » Mon Oct 15, 2007 6:02 am

[quote][quote]Slotback,
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Re: 787 unsafe?

Postby Slotback » Mon Oct 15, 2007 6:17 am

Lol, sorry I misworded something. A 717 at normal approach speed / flaps 25, will actually be at a very low power setting and will not be pointing its nose up any higher than any other airliner to fly, as with the A320. :)

However, I thought about what you said regarding that Boeings are known for their great climb performance...
TAM's airbus A319 can legally perform FLEX takeoffs at Santos Dumont (SBRJ, one of the shortest runways in Brazil) while the 737's must use full TOGA thrust and perform a brakes ON takeoff.

Eh, sorry.

I guess these generalisations about climb only work with specific aircraft.

An-225, did you notice any superior qualities of the 717 when you flew on them? Renember the tail number? Sorry but I've flown on this one 717 a number of times and kinda have an emotional connection to it (lol (LOL)). Thank got NJS Is keeping 717s in long term. :)
Last edited by Slotback on Mon Oct 15, 2007 6:37 am, edited 1 time in total.
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Re: 787 unsafe?

Postby an-225 » Mon Oct 15, 2007 8:28 am

Well...it was small...and the legroom was bad...and the pressure change at said "drop like a rock" ROD really hurt...but then again, the A320 flight on Ted was quite hot, cramped too, but seemed to have less maneuverability than the 717 (Impulse 717 = TIGHT turning circle, even with lots of room to spare, A320 just seemed to dawdle on as we descended towards KLAS, no traffic problems on either flight too).  :)

Nexus, in theory, the more noise a plane makes, the more it is powering up, whereas the 767 has to powerup to a high amount of throttle to maintain glideslope, at least into Sydney, the A330 makes only a whisper as it glides on in to the runway. Also, when I was flying on that A330, I noticed that the throttle was at least at flight idle by the relatively small kick in the back of my seat. The same can't be said for the 767, as I have not flown on it, but its lesser counterpart, the 737 had considerable kick to it. Not actual fact, but merely, and observation.  ;)
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Re: 787 unsafe?

Postby Nexus » Mon Oct 15, 2007 2:10 pm

AN-225. I am going to show these pictures and ask you to study them just for a second.
first one is an A330 couple of hundred feets above the threshold.
The second one is a B767 (landing in Brisbane actualy) in a similar scenario
Last edited by Nexus on Mon Oct 15, 2007 2:11 pm, edited 1 time in total.
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Re: 787 unsafe?

Postby matt2190 » Mon Oct 15, 2007 3:01 pm

I am just going to take a quick moment here to jump back to the original article . . . and the complaining fellow's comments (in the article) that the 787 would be dangerous in a crash:

Wow! I didnt know they made aircraft that were safe to crash. ;) ;) ;D
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Re: 787 unsafe?

Postby The Ruptured Duck » Mon Oct 15, 2007 8:34 pm

The fuselodge will burn with toxic fumes?  I can't think of an airplane that wouldn't.
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