Falcon 50/900 Information Needed

[Uncle Sparky]

Two Weeks! Don't worry, I made sure you were logged off for good.

Thanks.......never mind accusations of homosexuality, if people thought that I didn't know that a Falcon 50 has three engines I really would be embarassed!

 

[Lead Sled]

Yea! And when you get one, please have your boss call mine and tell him how nice of an airplane it is, and that he needs to get him one and get out of those god forsaken learjets!

Hey, we may be able to get you a deal on a nice Astra. I quit flying Lears 10 years ago. It was the happiest day of my life. (No more dragging baggage through the cabin.) It took me 7 years to be able to hold my head up straight in the cockpit.

'Sled

 

[G100driver]

Hey, we may be able to get you a deal on a nice Astra. I quit flying Lears 10 years ago. It was the happiest day of my life. (No more dragging baggage through the cabin.) It took me 7 years to be able to hold my head up straight in the cockpit.

'Sled

Funny, when got out of the Westwind and into the Astra it was the happiest day of my professional life as well. I absolutely LOVED flying the Gulfstream-100/Astra. It is a great airplane for the price. Take away the 2 problems it has (slats/flaps) and it is, in my opinion the best value in mid-sized jets.

Now, with that said ... when your boss gets that Falcon ??? you will have a new happiest day in your life. You will realize that you do not have to wear a headset in the cockpit to have a conversation. 90F and need to go 2000 miles outta TEB and cannot accept the Dalton departure, no problem. 100 knot headwind going to HI, no worries. Gotta stand up and stretch your legs and get a soda, go for it! All of the large cabin Falcon will suit these needs ... even the 2000 (EX). You are going to love it!

Good luck ... no matter what you are not going to loose! You are in the PERFCT situation.

 

[GVFlyer]

Okay my aircraft experience is in the Sub-sonic range(not that a sub-sonic aircraft doesn't posess a boundary layer) but if you don't mind, explain sub-boundary VG.

I'll answer your question, but I have to give you a little theory and history first.


In maneuvering conditions aircraft need to generate high lift coefficients to achieve required performance. This is either because only a component of lift is available to counter the aircraft weight, as in turning maneuvers, or because the aircraft speed needs to be low, as in landing and take-off. Most of this lift is generated on the wing’s upper surface, where the pressures are generally lower than at the wing trailing edge. Therefore there can be large positive pressure gradients on the wing. A possible consequence is that the boundary layer separates, causing, in turn, a loss of lift, high drag and buffeting. In high-speed maneuvers they may occur downstream of shock waves, causing bubbles that may burst or join up with trailing-edge separations to cause flow breakdown.



One method of flow control is the use of vortex generators. GV wing development and Reynold’s Number research was accomplished at NASA Langley in Virginia. Employment of new technology microvortex generators (MVGs) was pioneered on the GV wing. The following is an excerpt from a NASA press release.





One of the most widely applied concepts for flow control is vane-type, passive vortex generators that transfer high-energy fluid outside the boundary layer to the surface region inside the boundary layer. First introduced in 1947, vortex generators consist of a row of small plates or airfoils that project normal to the surface and are set at an angle of incidence to the local flow to produce an array of streamwise trailing vortices. These devices are used to energize the boundary layer such that boundary-layer separation is eliminated or delayed, and this can be used to enhance wing lift, improve control effectiveness, and/or tailor wing buffet characteristics at transonic speeds.



Led by John C. Lin, a team of Langley researchers dramatically improved the characteristics of VGs by developing smaller microvortex generators (MVGs) to produce streamwise vortices that more efficiently transfer momentum within the boundary layer. Langley’s research on MVGs began as a fundamental investigation of boundary-layer separation control in the early 1990s. Within that fundamental objective, researchers attempted to determine the minimum effective size for vortex generators. Langley organized an aggressive experimental program to obtain detailed information on the mechanism by which vortex generators reenergize the turbulent boundary layer and prevent separation. The resulting optimization to a sub-boundary-layer scale provided a major breakthrough in the fundamental understanding of the nature of vortex generator flow control and potential applications. The initial laboratory experiments were conducted in the Langley 20- by 28-Inch Shear-Flow Control Tunnel



In addition to industry interests in applications to commercial transport aircraft, the Langley-developed MVG concept has also been applied by the general aviation industry to enhance performance and high-lift characteristics. In a cooperative investigation with Gulfstream Aerospace Corporation, tests were conducted in the LTPT to improve the Gulfstream V high-lift geometry using microvortex generators in 1994 and 1995. In addition, during flight tests conducted in 1996 and 1997 by Gulfstream, the microvortex generators outperformed conventional vortex generators for controlling shock-induced separation. The Gulfstream V now incorporates MVGs on the outboard upper surfaces of its wing for enhanced cruise performance. With the MVGs installed, the Gulfstream V was able to achieve a higher maximum cruise speed, extend its operational range capability, and exhibit better controllability. The enhanced aerodynamic performance provided by MVGs allowed Gulfstream to meet their technical goals and assure a timely and successful product. As previously discussed, the Gulfstream V aircraft has set numerous domestic and world speed and performance records and was named the winner of the 1997 and 2004 Collier Trophy presented by the National Aeronautic Association



The next step in wing development will probably be the use of Sub Boundary Layer Vortex Generators (SBVG) which are a smaller VG than even the MVGs. They can be wedges, rotating vanes or counter-rotating vanes.



In wind tunnel testing it has been shown that SBVG devices with heights in the order of only one quarter of the boundary layer height can significantly reduce the size of regions containing turbulent boundary layer separated flow. The use of such devices would significantly reduce the parasite drag associated with flow control. The challenge is managing the length of the downstream vortex.



Another technology being investigated to control flow is the use of jets of air emerging at an angle from the wing surface to produce a similar type of vortex flow as traditional VGs. The air jet vortex generators (JVG) can be steady with time or pulsed in operation (PJVG) and offer active type flow control without the need of a protruding physical device like a VG on the wing surface.




GV

 

[Uncle Sparky]

Thanks for the info...

Another technology being investigated to control flow is the use of jets of air emerging at an angle from the wing surface to produce a similar type of vortex flow as traditional VGs. The air jet vortex generators (JVG) can be steady with time or pulsed in operation (PJVG) and offer active type flow control without the need of a protruding physical device like a VG on the wing surface.GV

I was always impressed by the idea of using bleed air to energize the wing and wondered why it never went further than it did . I never really gave much thought to the idea of fine tuning the direction of and delaying the separation of airflow by using the same kind of technology.

 

[GVFlyer]

Thanks for the info... I was always impressed by the idea of using bleed air to energize the wing and wondered why it never went further than it did . I never really gave much thought to the idea of fine tuning the direction of and delaying the seperation of airflow by using the same kind of technology.

Yes, the use of bleed air for boundary layer control on the F-4 was not a successful strategy and was abandoned. The technology is more mature today.

In reviewing my post I see that I omitted a couple of the benefits of VGs such as the opportunity to have wings of greater thickness or higher taper. This allows development of wings of lower weight and larger fuel volume.

GV

 

[GVFlyer]

The price of fuel is rediculous, hope to see it drop in the coming months!

Roger that! Our single largest cost of operation is fuel even though we have our own fuel farm. Beyond that, fuel costs are killing our industry - from the legacy carriers to the start-ups like Independence.

GV

 

[AA717driver]

Yeah, the price of fuel is through the roof, our budget is blown and we're gettin' nickel-and-dimed by the 'Expense Report Police'!

I had to airline on LOT last week for crissake! Doubt my 96.00Euro laundry bill from Nice is gonna fly...

Oh well, back to sex and bar-b-que!TC