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Teach me why I listen to Turboprop drivers always discussing airspeed.

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Not always true...

A tp doesn't usually have that much to gain by flying lots higher with respect to fuel burns and allowable altitudes so the typical best altitude is the highest altitude that you can still make 100 % of rated horsepower, that is if maximum TAS is your goal.

You will most often see tp pilots flying at their FASTEST altitude unless they are really trying to stretch range.

The ground speed discussion is not valid in the remarks that the tp pilots you overhear are talking about. In short, there is a higher percentage gain available for jets to climb than there is for turboprops.

I think I'm going to have to take issue with that. I don't have much time in King Airs, but the Metros and Jet Streams that I flew had tons to gain by climbing.

First, I can rarely reach 100% torque on any given day. So, flying at 100% power just isn't an option.

Second, the Garrett 331's burn a ton of fuel below 10, but sip fuel above 18. Most days I will indicate 1200 lbs/hr + just after takeoff, but I can always count on 500 lbs/hr or less in the flight levels. That is a very big change.

Third, ground speed is just fun to talk about when you are a turboprop guy...or hell...even just a pilot. Hitting 384 knots across the ground in level flight in a Metro is something to brag about. Of course, the 650 knots I did in a 35 was pretty hot sh!t too.

Back on point: What I'm getting at is that there is a very high percentage to gain in a turboprop. It may not be as high as some jets, but that doesn't mean that it isn't worth going up.

My tip of the day (an it is probably worth what you paid for it ;) ) do some digging and find out what IAS you need to make the TAS that will give you the best specific range. Maybe you'll get lucky and find out that at 10,000 it is 200 KIAS and that it drops 1 knot for every 500 feet you climb. I know I was pleased to find that out about the Metro.
 
Turbo prop guys talk about True Airspeed for many reasons. Most of the time it is due to the many modifications available to Turbo Props. Comparing notes about TAS is the only true comparison if you have paid for a speed upgrade on a Turbo Prop. Many of the routes flown in a turbo prop high Altitude is really not a factor.

For many Charter operators who may have a King Air on a wet lease, Speed is more important than the fuel flow. You want to beat the clock. If you quoted 1.2 hours and you fly the leg in 1.0, you increased profit because you only paid the owner 1.0, but billed 1.2.

As KSU said, our fuel flows are not as greatly effected as you are used to in the bigger aircraft.

The last consideration is ATC. Many times you can file for high 20's low 30's and ATC will just plain not give it to you. Mid 20's may be the best you get.

Now for the real answer. If you are climbing the ranks in the early stages of your pilot career and you just landed a job in a nice Corporate Turbo Prop, compared to the 170Kts Barron you were flying, 270-300Kts is very cool.
 
dude whoever is talking airspeeds at the FBO needs to get a life.

I am usually talking to the FBO girls or in the crew car at Outback eating
 
Hahaha I guess I'm passed the kewl stuff. I accidently started out on DC-8 as an FE with just an A&P and after that fours years of nostalgia have been going backwards ever since. Depends on how you look at it. The king air is nice though.
 
Hey...


As a pilot I care about is my speed across the ground depending on the altitude in still air first then as affected by the winds compared to my fuel flow.

Speed across the ground is what matters to me and in the jets I was on (DC-8, CRJ & 737) the higher we got the faster we go across the ground... and lower the fuel flow.

As the airspeed dwindles as we go higher per profile.... who cares that the airspeed is lower.... we are going 460kts across the ground at maybe 275 kts indicated on most jets.

.

Not exactly true. The higher you go in a jet the slower your groundspeed will be once you past the point of max rated power.

EX.. assuming winds are calm.

31,000 ft. TAS 425, GS 400, Fuel Flow 2,000 PPH
38,000 ft. TAS 450, GS 425, Fuel Flow 1,500 PPH
43,000 ft. TAS 415, GS 385, Fuel Flow 1,000 PPH

I feel the same way you do. I hear pilots all the time talking about TAS, etc. I could care less. I only look at GS also. But, as stated above, for performance mods etc, it is the only way to compare, and you really cant control GS.
 
OK tell me the aerodynamics and formulas to come up with NIL wind figures gives you a lower GS for a known TAS:

IE you say TAS 415 = GS 385 !

My understanding of ground speed is thats its the speed of an aircraft relative to the ground. It is the sum of the aircraft's true airspeed and the current wind... teaching and writing texts books for the last 20 years on this crap may have fried my brain but a 400kt TAS with no wind is a 400kt GS?


Unless I am wrong and missed something here.
 
Not exactly true. The higher you go in a jet the slower your groundspeed will be once you past the point of max rated power.

EX.. assuming winds are calm.

31,000 ft. TAS 425, GS 400, Fuel Flow 2,000 PPH
38,000 ft. TAS 450, GS 425, Fuel Flow 1,500 PPH
43,000 ft. TAS 415, GS 385, Fuel Flow 1,000 PPH

I feel the same way you do. I hear pilots all the time talking about TAS, etc. I could care less. I only look at GS also. But, as stated above, for performance mods etc, it is the only way to compare, and you really cant control GS.


Yes I look at it the same way.... We are looking for the best distance gone over the ground compared to least amount of fuel flow.....................could be higher or lower depending on the situation, variables, time of day traffic, possible holds, whether ATC's hair looked nice in the mirror today, and how much viagra the captain used the other day even if we are the captain...........................of course beyond all the theoretical bull we learn about in training throughout the years........ it all depends on -everything- temps, ice protection bled off the engines, how fast we want to get there and do we want the engines to quit once we touch down from fuel exhaustion, owner and passenger likes or comfort, turbulence and penetration speed etc etc etc. No need for book worms to jump up and down on their soap box.... this is about real life and monitoring the plane a nd tweaking your performance as a human not a computer.
 
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No need for book worms to jump up and down on their soap box.... this is about real life and monitoring the plane a nd tweaking your performance as a human not a computer.
Ummmm in real life if you cant understand the relationship between something as simple as tas and gs you really should rethink all that theoretical bull you learnt again...it might come in handy one day!
 

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