Airliners.net

grandtheftaero

RE: 737 Engine Net..?

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grandtheftaero

RE: What Is The Fan Diameter Of The GE F101

I don't know the exact numbers but <acronym title="Trans Asia Airways (Taiwan)">GE</acronym>'s website gives the max diameter of the engine. That's a ballpark for the fan diameter. <a href="http://www.geae.com/engines/military/comparison_turbofan.html" target="_blank">http://www.geae.com/engines/mil...

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grandtheftaero

RE: GEnx Engine

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grandtheftaero

RE: GEnx Engine

Admittedly, I'm biased toward <acronym title="Trans Asia Airways (Taiwan)">GE</acronym> but there is some serious baloney in this thread... <TABLE BORDER=0 ALIGN=CENTER WIDTH=95% style="border-top: 1pt #28455E solid;border-right: 1pt #1B2E3F solid;border-bottom: 1pt #1B2E3F solid;border-left: 1pt #2...

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grandtheftaero

RE: What Are They Used For?

Those are pitot tubes, angle of attack senors, outside air temp sensors. and icing sensors.

I believe that red circle is a static pressure tap. I hesistate to say for sure because of it's location close to the nose.

--Shane

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grandtheftaero

RE: What Is That Red Window?

This summer I was based of out Boeing Field as a flight test participant on WD001, the 772LR pictured above. That particular blank-off has an OAT sensor mounted in it (IIRC). The other side of the plane has a blank-off with both a pitot tube and an OAT sensor in it. Someone please correct me if I've...

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grandtheftaero

RE: Why No Emergency Slides On JetBlue A/c?

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grandtheftaero

RE: Seattle A.net Meet Aug 18-20 Wrapup Thread

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grandtheftaero

RE: Seattle A.net Meet Aug 18-20 Wrapup Thread

<TABLE BORDER=0 ALIGN=CENTER WIDTH=95% style="border-top: 1pt #28455E solid;border-right: 1pt #1B2E3F solid;border-bottom: 1pt #1B2E3F solid;border-left: 1pt #28455E solid;table-layout:fixed;border-spacing:0;padding:0;border-collapse: collapse;" bgcolor=#1E3951><tr><td><font size=2 face="ARIAL, Helv...

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grandtheftaero

RE: The Best User Names Ever

To quote the late Eazy-E, "It's all about makin' that GTA"

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grandtheftaero

RE: Seattle A.net Meet Aug 18-20 Wrapup Thread

For all of you who missed the good times... Friends, airplanes, sunshine, and greasy food all day <img src="http://www.grandtheftaero.com/PICT1790copy.jpg" width="256" height="192" border=0> Drinks and girls in questionable attire all night <img src="http://www.grandtheftaero.com/PICT1408copy.jpg" w...

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grandtheftaero

No Respect For Proprietary Information

Hello All, I don't mean to start a flame war here but I just wanted to state my opinion on some of the photos I see on this site. This summer I've had the privilege to be an observer aboard a particular flight test aircraft. While aboard, the crew politely asked me to not take photos of the test con...

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grandtheftaero

RE: Take A Tour Through A RR Engine!

This is way cool too: GEnx Theatre

http://www.geae.com/education/genx/theatre/genx_theatre_go.html

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grandtheftaero

RE: What Percentage Of A Turbofan's Power Is Jet

B747FE, Hmmm... you bring up a good point... but here's another perspective. At <acronym title="Trans Asia Airways (Taiwan)">GE</acronym>, for book-keeping purposes, we classify bypass air and core air by their point of origin. Under this convention, air that is bled from the compressor is considere...

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grandtheftaero

RE: What Percentage Of A Turbofan's Power Is Jet

Duke, JT8D ~ 0.9:1 - 1.7:1 PW4000 ~ 5:1 CF6 ~ 5:1 GE90 ~ 9:1 As a matter of consistency, bypass ratio refers to the ratio of air flow rate that bypasses the core to the air flow rate that enters the core. I guess you could extrapolate power terms from airflow but usually bypass ratio refers to air f...

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grandtheftaero

RE: Creative Tail Numbers

SpaceShipOne is N328KF.... that's 328,000 feet... N100KM was already taken.

--Shane

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grandtheftaero

RE: Can A 4 Engined A/C Take Off With 1 Engine?

This one might be able to <img src="/discussions/graphics/biggrin.gif" ALT="Big grin"> <center><a href="/open.file/313479/L/" target="_blank">View Large</a> <a href="/open.file/313479/M/" target="_blank">View Medium <IMG SRC=...

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grandtheftaero

National Test Pilot School In Mojave, California

I’ve been considering getting a masters degree and in my research I came across the NTPS. As far as I know they are only school to offer a Master of Science in Flight Test and Evaluation. I was wondering if anyone had any information about it other than what’s on their website <a href="http://www.nt...

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grandtheftaero

RE: Jet Engine Thrust Percentage

"The CFM56 a common turbine power plant, the 56 refers to 5.6 to 1 ratio of fan in relationship to the core." Actually CFM56 is a meaningless acronym. As you might know CFMI, the company that produces the CFM56, is a 50/50 joint venture between <acronym title="Trans Asia Airways (Taiwan)">GE<...

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grandtheftaero

RE: Window In The Lav On A380

""Bleedless Engines" and "Composite Structures" are all good and well but i think it was a big mistake on Boeings behalf not to exploit this unique selling point. A mistake which IMO, will cost them dearly." Oh dear Lord... it's a good thing that wasn't posted in the Tech/Ops Forum. <im...

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grandtheftaero

RE: Was The 757 Successful?

Greg said, "1. The need to certify P&W's on what should have likely been an exclusive <acronym title="Royal Air Force (United Kingdom)">RR</acronym> product;" Interesting... Can you explain why the 57 should have been exclusive to <acronym title="Royal Air Force (United Kingdom)">RR</acronym>...

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grandtheftaero

RE: Jet Engine Compressor Blades

...but I understand that compressor blades are not really designed as aerofoils. Actually, in the bad old days compressor blades were designed exactly like airfoils. The compressor would be "unrolled" and modeled as a so-called linear cascade. The blades were assumed to be two-dimensio...

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grandtheftaero

RE: TF39 Engine Question

"the first GEAE high bypass Tfan was the CF6" Negative. The TF-39 was <acronym title="Trans Asia Airways (Taiwan)">GE</acronym>'s first high-bypass turbofan. The TF-39 has what is called a stage-and-a-half fan configuration. With this arrangement, the TF-39 operated with a bypass ratio of abo...

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grandtheftaero

RE: 7E7 Engine Selection Guesses

"GE and <acronym title="Precision Air Services (United Rep. of Tanzania)">PW</acronym> are offering a brand new engine" Actually <acronym title="Trans Asia Airways (Taiwan)">GE</acronym>'s engine is a GE90-core derivative. So it's a "new" engine but not a new centerline. On an unrelated note....

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grandtheftaero

RE: DC-10-30 Engine Question.

What is the real point of this? Why do they need to add the extra metal to cover the front area?" The "extra metal" is called a crown. It is warmed by engine bleed air and prevents ice formation. All three nacelles have this feature. The reason that the engine is placed in the aft portion of ...

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grandtheftaero

RE: Elevator/Alieron Control On Flying Wing Designs

Elevator control is achieved the same way as it would in a regular airplane, i.e. a control surface is deflected and creates a moment about the CG of the aircraft. The only difference is that there is a much shorter moment arm between the control surface and the CG of the aircraft. Yaw is trickier. ...

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grandtheftaero

RE: All About Stick Shakers

Stick shaking is a function that has been built into airplanes even before the age modern electronic flight deck controls. Airplane wings have a characteristic called washout. This means that the angle of attack (AOA) at the wing root is greater than the AOA near the wing tip. With this arrangement,...

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grandtheftaero

RE: Series Of Turbofan-Turbojet Engine Questions

"Hold on, are you saying that provided the inlet issues were dealt with properly, then ANY jet engine can make a aircraft fly at ANY speed?" Yes, a gas turbine engine doesn't "care" what it's installed in (test cell, airplane, boat, powerplant, etc) or how fast it happens to be moving. The on...

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grandtheftaero

RE: Series Of Turbofan-Turbojet Engine Questions

I have to retract a previous statement I made. "And an afterburning turbofan in either arrangement is possible. You can build one where the bypass air does not enter the afterburner duct or you can build one where the two flows combine and enter the afterburner." While it is theoretically pos...

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grandtheftaero

RE: Series Of Turbofan-Turbojet Engine Questions

1. I'm not sure I understand this question. What the heck is "speed of thrust"? 2. There is no such thing as max speed for an engine. The engine will fly at whatever speed you need it to as long as the inlet is designed properly, i.e. the inlet properly slows the air from freestream velocity to a sp...

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grandtheftaero

RE: SFC For The Different 747-400 Engines

I've never really used thrust lapse rate before so I'm not sure if its a definite number that's associated with a particular engine model (like SFC) or an abstract quantity they put it textbooks to confuse students. In any case, I've found some stuff from Georga Tech's website that might be useful: ...

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grandtheftaero

RE: SFC For The Different 747-400 Engines

TO (ISA SLS) = Take Off (International Standard Atmosphere / Sea-Level Static) ISA - means that you are referencing the internationally accepted values for atmospheric pressure, temperature, speed of sound, etc. <acronym title="Rio Sul (Brazil)">SL</acronym> - means that you are using sea-level valu...

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grandtheftaero

RE: 777 Engine?

Those are nacelle strakes. Here is a nice explanation from Dick Shevell's AIAA paper "Aerodynamic Bugs: Can CFD Spray Them Away?" DC-10 wind tunnel tests showed a significant loss in maximum lift coefficient in the flap deflected configurations, with landing slat extension, compared to prediction...

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grandtheftaero

RE: 7E7 With Bleed Free Engines?

"by the way, around how much thrust will they have?"

The engine that GE is developing for the 7E7 is to be the future replacement for the CF6. So I assume that their thrust ratings are similar.

--Shane

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grandtheftaero

RE: SFC For The Different 747-400 Engines

Good point... in all my textbooks fuel flow is specified as mass flow. But at work we use weight flow. Just a case of "potayto" and "potahto". And you're right, I am nitpicking a bit. But I'm glad to see someone is agreeing with me. <img src="/discussions/graphics/biggrin.gif" ALT="Big grin"> -...

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grandtheftaero

RE: SFC For The Different 747-400 Engines

"Give us an example where it doesn't work." I can't... you can plug the numbers into a calculator any way you want and get the right answer, just as long as you follow the correct order of arithmetic operations. But that wasn't my point. Bio15 has asked for a DEFINITION of SFC. What he is get...

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grandtheftaero

RE: SFC For The Different 747-400 Engines

"Either way works. There's no one right way." EITHER WAY DOES NOT WORK!!! The math might turn out to be the same (by sheer dumb luck) but the physics behind it doesn't. If you really want to understand SFC (or anything other performance metric for that matter) you'd better know what it really...

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grandtheftaero

RE: SFC For The Different 747-400 Engines

"SFC of an engine is the lbs. of fuel consumed per pound of thrust produced per hour. That is, "lbs. fuel/lbf/hr" ."

Actually SFC is pounds of fuel consumed per hour per pound of thrust (lb/hr/lb). That is why you sometimes see SFC in units of 1/hr.

--Shane

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grandtheftaero

RE: Is There Any Aircraft That Uses An Un-ducted Fan?

"Was the UDF project dismissed or is there still some research being done?" The UDF was abandoned by <acronym title="Trans Asia Airways (Taiwan)">GE</acronym> many years ago. I think other companies stopped research with their advanced turboprop programs, too. If you look at any technical pap...

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grandtheftaero

RE: Is There Any Aircraft That Uses An Un-ducted Fan?

Slow down, Prebennorholm... there are a number of half-truths here... "The way to produce a better SFC on the UDF was basically the increased fan diameter." You're on the right track... the way to reduce SFC is actually increased bypass ratio. "The <acronym title="Trans Asia Airways (Taiwa...

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grandtheftaero

RE: Is There Any Aircraft That Uses An Un-ducted Fan?

N685FE and Ben, great call on the Antonov! I totally forgot about it. FlightSimFreak, the UDF is a turboprop. As I alluded to in an earlier post, the UDF was GE's entry into NASA's Advanced Turboprop Program. The purpose of the ATP was to develop turboprops that could run at higher Mach numbe...

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grandtheftaero

RE: Is There Any Aircraft That Uses An Un-ducted Fan?

Economics had a lot to do with it, too. The UDF was designed with lower SFC in mind. With the price of petroleum no longer a critical issue near the end of NASA's Advanced Turboprop Program study, airlines didn't see any reason to build airplanes with unducted fan engines. On a related note... The S...

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grandtheftaero

RE: Prop Flow Question

"I heard from a proffessor that there is no possible way for a prop propelled plane to go much faster than a jet airliner" I think it depends on your definition of a prop-driven plane. Unducted fan research in the 80's would have brought advanced turboprop engines to big jetliners. I believe ...

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grandtheftaero

RE: A Question About The B2

DUDE!!! Flaperons would be for roll control NOT yaw control. That's why they are called flaperons not flaperrudders or whatever silly name you can think of. Yaw control in the B2 is provided by a device called a drag rudder. They are attached at the trailing edge where the red circle is located in t...

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grandtheftaero

RE: Prop Flow Question

Lehpron, I was assuming, from the way you worded your question, that you took symmetric to be with respect to the LE and <acronym title="Lithuanian Airlines">TE</acronym>, not the concave and convex sides of the blade, which is what SlamClick is referring to. Please let us know what you are referrin...

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grandtheftaero

RE: Prop Flow Question

I'm not sure if the blade is "symmetrical" with respect to LE and <acronym title="Lithuanian Airlines">TE</acronym> geometry. I think you're right about the flow traveling from <acronym title="Lithuanian Airlines">TE</acronym> to LE during reverse thrust though. Sure the blade probably isn't optimiz...

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grandtheftaero

RE: Prop Flow Question

"does the fan develop thrust against the wind or does it simply decelerate the flow creating some kind of low pressure region behind the prop" Sounds like the same thing to me. I think you're just overthinking the problem. The prop is doing the same thing in reverse pitch as it is in forward ...

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grandtheftaero

RE: BWB Is Not A Flying Wing?

Dude, the fuselage most definitely produces lift. Even conventional tube fuselages produce lift. If you look at the cross section of the BWB fuselage you'll see that it's actually a giant supercrtical airfoil. Even at zero alpha it would produce lift.

--Shane

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grandtheftaero

RE: LA World Airports (LAWA)?

Did LAWA use to be the Los Angeles Dept. of Airports?

[Edited 2004-01-11 19:32:38]

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grandtheftaero

RE: Cones On Jet Engines?

FDXmech,

You're very welcome! And no problem with the first-name usage

--Shane

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