The official aviation quiz topic!

realplaneshaveprops · Post by **realplaneshaveprops** » 12 Dec 2005, 20:11

So when the engines are turning clockwise (right), both engines develop an equal amount of thrust. At low airspeed and high power conditions, the downward moving propeller blade of each engine develops more thrust than the upward moving blade. This asymmetric propeller thrust or "P-factor," results in a center of thrust at the right side of each engine. The yawing force of the right engine is greater than the left engine because the center of thrust is much farther away from the center line of the fuselage - it has a longer level arm. Thus, when the right engine is operative and the left engine is inoperative, the yawing force is greater than in the opposite situation of a "good" left engine and a "bad" right engine. In other words, directional control may be difficult when the left engine (the critical engine) is suddenly made inoperative.

Koen

Avro · Post by **Avro** » 12 Dec 2005, 20:42

Totally correct Koen 8)

Chris

SN_Bigbirdy · Post by **SN_Bigbirdy** » 12 Dec 2005, 22:15

All together : "Hail Koen, Hail Koen,....you :rock: "

realplaneshaveprops · Post by **realplaneshaveprops** » 14 Dec 2005, 16:28

What are the differences between the 737-200 and the 737-200 Adv?

Koen

fokker_f27 · Post by **fokker_f27** » 14 Dec 2005, 17:51

The 732 advanced is stronger.
Slightly more aerodynamic.

Avro · Post by **Avro** » 14 Dec 2005, 18:05

Several features were changed:

The advanced version has a longer engine exhaust nacelle (reducing drag) and wider Kruger flaps. THe Kruger flaps on the -200Adv go up until the root of the wing while on the -200 they stop before.

Further more the -200Adv was fitted with new engines, which were more powerful and able to increase the MTOW of the plane.

Also new on the Advanced were the Autobrake and antiskid features and some more advanced flap settings.

Chris

realplaneshaveprops · Post by **realplaneshaveprops** » 14 Dec 2005, 18:08

I would like to read more technical stuff.

Boeing did some modifications (improvements) to the original -200 before the -200Adv was launched. So my question was, what was modified to the already modified -200 to make it the -200Adv?

I tried to explain it better and to make it easier, hopefully I was succesful in my mission!

Edit: this was only in reply to Fokker_f27

Koen

realplaneshaveprops · Post by **realplaneshaveprops** » 14 Dec 2005, 18:30

Chris, you're the next one to ask a question. You gave some good answers.

However: the longer nacelles, was a modification to the original -200

Modification for the -200Adv
- New leading edge flap sequencing
- Increased droop of outboard slats
- Extension of the (inboard) Krueger flap

- MTOW increase of 2268kg
- autobrake
- improved anti-skid
- upgrade to JT8D-15 engines with 15.500lbs thrust
- In 1973 when noise was becoming a factor, the nacelle was acoustically lined by Boeing and P&W swapped one fan stage for two compressor stages in the JT8D-17 while increasing thrust to 16,000Lbs. The JT8D got up to 17,400Lbs thrust on the -17R.

Increase in ceiling to 37.000ft
Increase in max differential pressure from 7.5 to 7.8psid to accommodate higher ceiling

Koen

Avro · Post by **Avro** » 14 Dec 2005, 20:50

What is the purpose to have the patches of small holes in the intakes of engines ?

here's a picture to illustrate: http://www.airliners.net/open.file/324255/L/

Chris

realplaneshaveprops · Post by **realplaneshaveprops** » 15 Dec 2005, 15:23

Those are acoustic panels, to reduce the soundlevels of the engine

Koen

Avro · Post by **Avro** » 15 Dec 2005, 15:25

correct, your turn.

Chris

realplaneshaveprops · Post by **realplaneshaveprops** » 15 Dec 2005, 19:15

What happens when for example the number 2 engine fire handle of a RJ85 is pulled.

Extra info: the number 2 engine provides only hydraulic power to the aircraft, no electrical power.

Koen

Avro · Post by **Avro** » 15 Dec 2005, 21:49

realplaneshaveprops wrote: Extra info: the number 2 engine provides only hydraulic power to the aircraft, no electrical power.

I don't have the hydraulic system of the RJ plane so I can only guess:

If engine #2 down --> Engine pump of yellow system is down.
If I'm not mistaken an AC electrical pump will take up the work of the engine pump for the yellow system on the RJ.

I'll try to find a scheme of the hydraulic system of the RJ to have the correct answer though

Chris

realplaneshaveprops · Post by **realplaneshaveprops** » 15 Dec 2005, 22:37

No no no, what happens the moment you pull the fire handle.

Sorry if my question wasn't clear.
Tomorrow I will explain the RJ's hydraulic system if you want

Koen

Avro · Post by **Avro** » 15 Dec 2005, 22:51

realplaneshaveprops wrote:No no no, what happens the moment you pull the fire handle.

Oh ok , sorry I didn't read it very well

Tomorrow I will explain the RJ's hydraulic system if you want

That would be great. Because I don't know the systems of the RJ very well

Anyway here is my second try, but I'm not sure since I'm not familiar with the procedures and systems on the RJ:

When you pull the fire handle the following will happen (not in a particular order):

- Closing of fuel shut-off valve
- Closing engine bleed air valve
- Closing supply for hydraulic engine driven pump
- Arming firing circuits and allowing fire switches to be rotated for the discharge

Chris

realplaneshaveprops · Post by **realplaneshaveprops** » 16 Dec 2005, 20:41

You're answer is 100% correct

When pulled to its limit of travel:

- The engine bleed air isolation valve is closed
- The engine driven hydraulic pump isolation valve closes
- The engine fuel low pressure valve is closed

If fire persists, the firehandle is turned left or right through 90° causing:
The discharge of the number 1 or 2 fire bottle, as selected, and illumination of the associated fire extinguisher used annunciator.

So you're the next one to ask a question

Koen

Avro · Post by **Avro** » 16 Dec 2005, 20:50

Ok let's switch to the principle of the Airco systems of planes.

It's not for a specific plane I'm talking but the general principle of a simple airco system.

Hot bleed air is taken from the engine and will enter the so called pack. when leaving the pack the air can be used for the cabin.

What I want you to explain is what's happening in the pack.

A little tip: 3 main things happen in the pack.

Chris

MiStEr-T · Post by **MiStEr-T** » 20 Dec 2005, 04:12

My first try in this quiz

Inside the pack, bleed air is cooled by ram air through heat exchangers and an air cycle machine. A water separator collects water condensed by the cooling process to avoid icing.

TBK :jump:

abishay · Post by **abishay** » 20 Dec 2005, 06:55

I dont think im surpose to be in this quiz because i really dont anything of how the plane works( still 2 more years till i go and learn aeronutical engineering

) but i do know some stuff about plane engines

hope thats enough to be in this

Avro · Post by **Avro** » 20 Dec 2005, 09:19

MiStEr-T wrote: Inside the pack, bleed air is cooled by ram air through heat exchangers and an air cycle machine. A water separator collects water condensed by the cooling process to avoid icing.

Inside the pack the hot bleed air will be divided into two. One part will indeed will be colled with ram air through a heat exchanger and then expanded trhough a turbine. The super cooled air will then go through a water spearator and will be mixed with the other part of the bleed air. This is done to attain the desired temperature.

Your turn MiStEr-T !!

hope thats enough to be in this

You just need to answer the questions to be in this

Nothing more

Chris