Go Back  PPRuNe Forums > Flight Deck Forums > Tech Log
Reload this Page >

Pointless discussion for the cruise

Wikiposts
Search
Tech Log The very best in practical technical discussion on the web

Pointless discussion for the cruise

Thread Tools
 
Search this Thread
 
Old 18th Aug 2010, 06:15
  #1 (permalink)  
Thread Starter
 
Join Date: Jan 2007
Location: Up North UK
Posts: 95
Likes: 0
Received 0 Likes on 0 Posts
Pointless discussion for the cruise

There you are at FL370, fed and watered, with a couple of hours to go to ToD when a flying insect wakes itself up and gets airborne from somewhere forward of the pedals ...

Does this creature contribute to the all-up weight of the aircraft whilst it is flying (within the aircraft), or only when it alights on something?
Pontius's Copilot is offline  
Old 18th Aug 2010, 07:01
  #2 (permalink)  
 
Join Date: Jul 2001
Location: Gold Coast
Age: 58
Posts: 1,611
Received 0 Likes on 0 Posts
Yes.
(10ch)
18-Wheeler is offline  
Old 18th Aug 2010, 08:39
  #3 (permalink)  
 
Join Date: Dec 2000
Location: on the golf course (Covid permitting)
Posts: 2,131
Likes: 0
Received 0 Likes on 0 Posts
Of course it counts, just as the weight of the air on board the aircraft counts (about 1 tonne on a B747 iirc).

You must have short cruise segments if that keeps you occupied
TopBunk is offline  
Old 18th Aug 2010, 09:24
  #4 (permalink)  
 
Join Date: May 2002
Location: Sale
Posts: 374
Likes: 0
Received 0 Likes on 0 Posts
They did the experiment on Mythbusters but using birds flying around inside a truck.

When the birds were flying they imparted the downforce on the air that pushed down on the truck, so there was no change in weight.

FIS
Field In Sight is offline  
Old 18th Aug 2010, 11:16
  #5 (permalink)  
 
Join Date: Aug 1998
Location: Ex-pat Aussie in the UK
Posts: 5,795
Received 116 Likes on 56 Posts
I you're bored in the cruise, you can always try a bit of Autopilot kerplunk

https://www.pprune.org/jet-blast/360...ml#post4683919
Checkboard is offline  
Old 18th Aug 2010, 11:34
  #6 (permalink)  
 
Join Date: Aug 2000
Location: UK
Posts: 3,648
Likes: 0
Received 1 Like on 1 Post
You must have short cruise segments if that keeps you occupied
True enough, the physics need not take long. But for the rest of the segment you could discuss whether your observation implies that the following is a really bad definition of an 'aircraft'.

‘aircraft’ means any machine that can derive support in the atmosphere from the reactions of the air other than the reactions of the air against the earth’s surface.
bookworm is offline  
Old 18th Aug 2010, 15:23
  #7 (permalink)  
 
Join Date: Apr 2009
Location: `
Posts: 309
Likes: 0
Received 0 Likes on 0 Posts
I wonder if the answer turns out to be 42?
Biggles78 is offline  
Old 19th Aug 2010, 02:03
  #8 (permalink)  
 
Join Date: Jun 2010
Location: Brisbane, Australia
Posts: 304
Likes: 0
Received 0 Likes on 0 Posts
So...the Wright Bros machine that flew all that time ago wasn't actually an aircraft at all...since the entire flight was done in ground effect!

EW73 is offline  
Old 19th Aug 2010, 04:45
  #9 (permalink)  
 
Join Date: Feb 1998
Location: Formerly of Nam
Posts: 1,595
Likes: 0
Received 0 Likes on 0 Posts
1. Your flying around with 300 POB. Suddenley a pax dies of a heart attack. Are you required to then revise your POB to 299?

2. Enroute over a ocean ETOPS with a full pax load. A woman gives birth prematurly on board. Paxing doctor says the tiny kid is alive and doing well and can easiley withstand the remaining 3 hours to destination. But the additional baby now exceeds the number of child life vests and cots available. Nearest airport is 2 hours from PPOS off track. Continue or divert?

3. Through a series of personal misfortunes a fit and strong pax is on top of the wing of a heavy departing 747. He lies head down and holds on to the vortex generators for dear life during the take-off. V2 is 170kt, enroute climb 320kt to FL310. He will either fall off the wing from increasing airspeed or die from cold and lack of oxygen (and then fall off). Which will occur first?

4. Enroute over the ocean with 6 hours to go. Using only 3 HF calls how do you start World War III?
Slasher is offline  
Old 19th Aug 2010, 07:50
  #10 (permalink)  
 
Join Date: Nov 2002
Location: Heart of Europe
Posts: 198
Likes: 0
Received 0 Likes on 0 Posts
1. Is it inherently dangerous to have a flying insect in the cockpit at FL350?

2. Shall we order F/A to cockpit with insect spray. Don oxy masks and give it a go with the spray.

3. What are the implications of spraying insect spray in the cockpit with all gizmos on? Fire? Smoke?

4. How fast will the fits from a Malaria fever set in? Could it incapacitate the cockpit crew?

5. What family of insect? Precise name in latin?

6. Shall we make a speech and look if a biologist specializing in insects is on board?

error_401 is offline  
Old 19th Aug 2010, 14:58
  #11 (permalink)  
 
Join Date: Jan 2005
Location: France
Posts: 2,315
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Slasher
1. You're flying around with 300 POB. Suddenley a pax dies of a heart attack. Are you required to then revise your POB to 299?
Nice one...
What does 'POB' formally stand for? "People on board"?
If so, it doesn't say whether they are alive or dead, so your POB remains at 300.

Leads to another question... if you have a coffin in the hold with a body being repatriated for burial, do you have to include that in the 'POB' count?

And if you use that other quaint term 'SOB' ("Souls on Board"), what happens to the soul when the pax dies? Can you be sure it's left the aircraft? Or might it hang on to stay near to the body and not leave until later?

CJ
ChristiaanJ is offline  
Old 19th Aug 2010, 15:24
  #12 (permalink)  
 
Join Date: Jan 2009
Location: Europe
Posts: 56
Likes: 0
Received 0 Likes on 0 Posts
Leads to another question... if you have a coffin in the hold with a body being repatriated for burial, do you have to include that in the 'POB' count?
Yes. The reason for this is in case of accident, you'll also find the body of the coffin

4. Enroute over the ocean with 6 hours to go. Using only 3 HF calls how do you start World War III?
I got curious now...
zedoscarro is offline  
Old 19th Aug 2010, 15:37
  #13 (permalink)  
 
Join Date: Jan 2004
Location: Canada
Age: 63
Posts: 5,209
Received 134 Likes on 61 Posts
If you want to pursue a really pointless discussion you could always talk about the chances that the job of flying airplanes will ever return to it's former glory
Big Pistons Forever is offline  
Old 19th Aug 2010, 16:41
  #14 (permalink)  
 
Join Date: Jun 2006
Location: Europe
Posts: 716
Likes: 0
Received 0 Likes on 0 Posts
To make the judicial bits easier, the heart attack guy will continue to live until you land. Then he is pronounced. Makes everything a lot easier.
bfisk is offline  
Old 19th Aug 2010, 18:03
  #15 (permalink)  
Psychophysiological entity
 
Join Date: Jun 2001
Location: Tweet Rob_Benham Famous author. Well, slightly famous.
Age: 84
Posts: 3,270
Received 37 Likes on 18 Posts
g-u-y, pronounced guy. He probably walked with a l-i-m-p, pronounced limp.


Sorry Spike.


This thread is getting silly . . . you'll be really welcome down in Jet Blast.
Loose rivets is offline  
Old 19th Aug 2010, 22:44
  #16 (permalink)  
 
Join Date: Jul 2001
Location: Gold Coast
Age: 58
Posts: 1,611
Received 0 Likes on 0 Posts
1. Your flying around with 300 POB. Suddenley a pax dies of a heart attack. Are you required to then revise your POB to 299?

2. Enroute over a ocean ETOPS with a full pax load. A woman gives birth prematurly on board. Paxing doctor says the tiny kid is alive and doing well and can easiley withstand the remaining 3 hours to destination. But the additional baby now exceeds the number of child life vests and cots available. Nearest airport is 2 hours from PPOS off track. Continue or divert?

3. Through a series of personal misfortunes a fit and strong pax is on top of the wing of a heavy departing 747. He lies head down and holds on to the vortex generators for dear life during the take-off. V2 is 170kt, enroute climb 320kt to FL310. He will either fall off the wing from increasing airspeed or die from cold and lack of oxygen (and then fall off). Which will occur first?

4. Enroute over the ocean with 6 hours to go. Using only 3 HF calls how do you start World War III?

Excellent! Love your work.

Another good one ...
You're right on maximum ramp weight for departure - should you allow the extra ground crew on board and thus exceed max ramp weight?
18-Wheeler is offline  
Old 19th Aug 2010, 23:42
  #17 (permalink)  
 
Join Date: Jan 2005
Location: France
Posts: 2,315
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by 18-Wheeler
You're right on maximum ramp weight for departure - should you allow the extra ground crew on board and thus exceed max ramp weight?
Of course not.
Enough of that "extra ground crew" in the back cabin, and you'll find yourself with a tailsitter.

CJ
ChristiaanJ is offline  
Old 20th Aug 2010, 00:36
  #18 (permalink)  
 
Join Date: Mar 2007
Location: Cardiff UK
Age: 70
Posts: 118
Likes: 0
Received 0 Likes on 0 Posts
In the 19th century some bright spark set out to prove that the soul existed. So he weighed people just about to die and then immediatley after and found that their weight fell by a quarter of an ounce! Therefore in the case of the cardiac death should you reduce the ZFW to allow for this weight loss?
Regards
Nick

Last edited by Nick Thomas; 20th Aug 2010 at 00:38. Reason: punctuation
Nick Thomas is offline  
Old 20th Aug 2010, 04:03
  #19 (permalink)  
Psychophysiological entity
 
Join Date: Jun 2001
Location: Tweet Rob_Benham Famous author. Well, slightly famous.
Age: 84
Posts: 3,270
Received 37 Likes on 18 Posts
I seem to remember that the experimental results were declared void by the finding that their underpants had increased in weight.
Loose rivets is offline  
Old 20th Aug 2010, 04:24
  #20 (permalink)  
 
Join Date: Feb 2000
Location: 500 miles from Chaikhosi, Yogistan
Posts: 4,295
Received 139 Likes on 63 Posts
A related topic (about the insects in the cockpit) from a while ago.

http://www.pprune.org/dg-p-general-a...-question.html
compressor stall is offline  


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.