Real TAS for Planes?

[SoCal RV Flyer]

You ask about 'real' world speeds; http://www.flightaware.com will tell you what typical groundspeeds specific N-numbers are doing, if you know some you want to look up. And finding random aircraft shouldn't be too difficult.
Many a/c will fly A to B then return to A, a short time later - so you can get an idea of real world average GS's. (for very recent flights you can look up winds aloft to see how that was affecting their GS)
Its a good tool to see what an aircraft you are going to purchase has been doing too, helps blow through the sales pitch lies (also good to see if your buddies are giving fish stories when they talk about what their aircraft can do, lol)

I know some people use flightaware to monitor all a/c of one type, but I am not sure how to do that. Somehow they can type in "Cessna 172" somewhere and see all that are airborne at any one time and from there, select one and view the track log.
Maybe you have to pay extra for this but I think you an also get an alert anytime one of these aircraft in the entire fleet are detected in the NAS by ATC radar.

That will give you some idea.

For me, there's a 15-20 kt delta in TAS between making time on a cross-country flight, or cruising on a 30-minute run. On shorter missions, I want to slow down and enjoy the flight for a longer time! 100LL savings pay for part of breakfast.

 

[Pilawt]

Have you never seen 112 KIAS in cruise on a Warrior II at 75% power?

I have.

 

[David Megginson]

I have.

View attachment 81447

I've found that the majority of people who claim Cherokees (and other similar non-complex planes) go 10-20 kt slower than POH speeds are the same people who say things like "I always cruise at 2400 rpm". So, um, yeah, that's the problem.

 

[David Megginson]

That will give you some idea.

For me, there's a 15-20 kt delta in TAS between making time on a cross-country flight, or cruising on a 30-minute run. On shorter missions, I want to slow down and enjoy the flight for a longer time! 100LL savings pay for part of breakfast.

Agreed. If I'm just out to look at the scenery and add 1.5 to my logbook, then I cruise at 55% power. Why go fast and burn extra gas for no good reason?

 

[MajorTurbulence]

I just did a performance check for my Archer II and my TAS was 133-134 at DA 10,000 and 9,000 at wide open throttle with mixture 100deg rich of peak at slightly more than 10.5 gph. I was lightly loaded but from past experience with multiple trips a full gross, that speed does not change, or maybe subtract one knot probably because I’m often at aft cg at max gross loadings.

I think using historical FlightAware data is not a good representation of TAS given to variations in what power settings are being used by those flights. When I fly distances now, in contrast to how I did it earlier in my flying career, I’m often backing off to 65% power at peak EGT to extend my range and minimize fuel stops with often minimal decreases in my block time. Extending the range can help avoid an additional fuel stop in certain situations and actually improve your time to destination.

I do think that learning to fly more efficiently to maximize TAS or whatever you are trying to do comes with experience, as you might expect. I remember those many early hours of not really flying the numbers well because insecurities in my leaning technique and fuel flow rates, so I would often increase my margins. Getting an engine monitor and fuel flow will greatly add to your expertise in flying the numbers. And flying long trips with experienced pilots will jump start those abilities instead of the slow dicking around method. For some it may be hard to get the requisite experience in the low time rental arena if you haven’t already developed the expertise. It really helps to get to know your airplane, and the case for private ownership is an obvious big help.

Oh, I almost forgot, and this was mentioned by others that if you don’t have an accurate Tach, you don’t really know your power setting. My stock Piper tach was found to be running 175 less than actual, so I was flying at higher settings than expected. Get yourself a cheap hand held digital tach, or get one installed to help you know what you are really doing.

 

[N1120A]

The Warrior II POH says 127 KTAS at around 7,500 ft DA, mid-weight (2,300 lb), with wheel fairings on. I've never quite managed that.

When I'm cruising a few hundred lb below max gross (2,440 lb) at 75% power, in smooth air, I see 112 KIAS on the ASI, which is 110 KCAS. If you're at 7,500 ft pressure altitude with an OAT of 0C, 110 KCAS is abou 124 KTAS.

Have you never seen 112 KIAS in cruise on a Warrior II at 75% power?

Never

 

[David Megginson]

Never

When you're flying between 7,000 and 8,000 ft density altitude in a Warrior II (1978 or later) in smooth air

1. What's your gross weight?
2. What indicated airspeed do you see on the ASI?
3. What RPM do you see on the tachometer?
4. Do you have the wheel fairings installed?

That might help us diagnose your issue.

 

[David Megginson]

I just did a performance check for my Archer II and my TAS was 133-134 at DA 10,000 and 9,000 at wide open throttle with mixture 100deg rich of peak at slightly more than 10.5 gph. I was lightly loaded but from past experience with multiple trips a full gross, that speed does not change, or maybe subtract one knot probably because I’m often at aft cg at max gross loadings.

I think using historical FlightAware data is not a good representation of TAS given to variations in what power settings are being used by those flights. When I fly distances now, in contrast to how I did it earlier in my flying career, I’m often backing off to 65% power at peak EGT to extend my range and minimize fuel stops with often minimal decreases in my block time. Extending the range can help avoid an additional fuel stop in certain situations and actually improve your time to destination.

I do think that learning to fly more efficiently to maximize TAS or whatever you are trying to do comes with experience, as you might expect. I remember those many early hours of not really flying the numbers well because insecurities in my leaning technique and fuel flow rates, so I would often increase my margins. Getting an engine monitor and fuel flow will greatly add to your expertise in flying the numbers. And flying long trips with experienced pilots will jump start those abilities instead of the slow dicking around method. For some it may be hard to get the requisite experience in the low time rental arena if you haven’t already developed the expertise. It really helps to get to know your airplane, and the case for private ownership is an obvious big help.

Oh, I almost forgot, and this was mentioned by others that if you don’t have an accurate Tach, you don’t really know your power setting. My stock Piper tach was found to be running 175 less than shown, so I was flying at higher settings than expected. Get yourself a cheap hand held digital tach, or get one installed to help you know what you are really doing.

I did that, and found that my tach was overreading by about 50 rpm (when it said 2,600 rpm, I was really only at 2,550). As you mention, that's one (of many) reasons you won't get book numbers, because you're flying at a weaker power setting than you thought.

 

[David Megginson]

I think using historical FlightAware data is not a good representation of TAS given to variations in what power settings are being used by those flights.

Even if you flew every flight at the exactly same density altitude and power setting, your average ground speed from an aviation GPS app would still be at least 5-10 kt slower than your TAS, because most of us spend more time in headwinds than tailwinds.