are we interested in air speed or ground speed ? Does it matter
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are we interested in air speed or ground speed ? Does it matter
Just curious how people feel about this. I mean with the wind you planes ground speed is consiberly more as it speeds past you. That ground speed is surley the refection how fast you model feels.?
#2
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RE: are we interested in air speed or ground speed ? Does it matter
If I can feel the air pound my chest when it goes by I'm good
When we did our rally we used a radar gun so I guess that's pretty close to ground speed. For me it isn't a big deal just a refrence point to base how crazy I am. [sm=what_smile.gif]
When we did our rally we used a radar gun so I guess that's pretty close to ground speed. For me it isn't a big deal just a refrence point to base how crazy I am. [sm=what_smile.gif]
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RE: are we interested in air speed or ground speed ? Does it matter
ORIGINAL: mk1spitfire
Just curious how people feel about this. I mean with the wind you planes ground speed is consiberly more as it speeds past you. That ground speed is surley the refection how fast you model feels.?
Just curious how people feel about this. I mean with the wind you planes ground speed is consiberly more as it speeds past you. That ground speed is surley the refection how fast you model feels.?
To me, ground speed is irrelevant information - I am only interested in how fast it is moving through the air it's in, since how it feels and responds in the air is a direct reflection of its airspeed. As to visual impression, if I am flying a fast airplane I am not sure I even am aware of the difference in ground speed upwind or downwind to be honest, although I guess I might notice it from time to time. With a slow airplane then sure it's noticable, but that does not apply here.
MJD
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RE: are we interested in air speed or ground speed ? Does it matter
You say that with the wind the airplane feels how fast its ground speed is? That is not accurate. I fly full scale planes also and I will tell you that if a plane has a 45 kts tail wind and you are already flying at 150 knots (Airspeed) then your (groundspeed) is 195 knots but your airspeed stays. The airplane does not know or feel that it is going that extra 45 kts therefore it is not affecting anything other than ground speed fuel efficiency, and getting somewhere much faster. {An example} (Never exceed speed) for a full scale airplane is different in that since because if your never exceed speed is 175 and you are going 195 ground speed the airplane doesn't know that you are going over 170 kts because it thinks your still going 150 kts, so therefore you are not exceeding the aircrafts limits.
Very simple actually.
Matt
Very simple actually.
Matt
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RE: are we interested in air speed or ground speed ? Does it matter
When a car or fast motorbike passes you at high speed, you notice that. .!!!!
The bonus of ground speed is the downwind leg is percieved to be faster with aircraft.
As you watch and fly your plane as it zooms past yourself the ground speed is very relevant.
These gizmo that measure speed are airspeed so guess you just add wind speed on for ground speed.
Are doppler checkers airspeed only?
The bonus of ground speed is the downwind leg is percieved to be faster with aircraft.
As you watch and fly your plane as it zooms past yourself the ground speed is very relevant.
These gizmo that measure speed are airspeed so guess you just add wind speed on for ground speed.
Are doppler checkers airspeed only?
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RE: are we interested in air speed or ground speed ? Does it matter
ORIGINAL: Patterndude1
You say that with the wind the airplane feels how fast its ground speed is? That is not accurate. I fly full scale planes also and I will tell you that if a plane has a 45 kts tail wind and you are going 150 knots then your groundspeed is is 195 knots but your airspeed stays. The airplane does not know or feel that it is going that extra 45 kts therefore it is not affecting anything other than speed. {An example} (Never exceed speed) for a full scale airplane is different in that since because if your never exceed speed is 175 and you are going 195 ground speed the airplane doesn't know that you are going over 170 it thinks your still going 150, so therefore you are not over the stress limit.
Very simple actually.
Matt
You say that with the wind the airplane feels how fast its ground speed is? That is not accurate. I fly full scale planes also and I will tell you that if a plane has a 45 kts tail wind and you are going 150 knots then your groundspeed is is 195 knots but your airspeed stays. The airplane does not know or feel that it is going that extra 45 kts therefore it is not affecting anything other than speed. {An example} (Never exceed speed) for a full scale airplane is different in that since because if your never exceed speed is 175 and you are going 195 ground speed the airplane doesn't know that you are going over 170 it thinks your still going 150, so therefore you are not over the stress limit.
Very simple actually.
Matt
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RE: are we interested in air speed or ground speed ? Does it matter
Why would ground speed be relevant in your oppinion? Ground speed doesn't really matter for an rc airplane.
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RE: are we interested in air speed or ground speed ? Does it matter
If something whizzes past you, wether its a car on the ground or a rc model 1 foot off the deck then the speed of that object is detected by the eye as shifting fast reletive to ground speed.
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RE: are we interested in air speed or ground speed ? Does it matter
It's all about bragging rights [8D]
Again back to our rally we took readings from two readings in each direction and gave an average of the fastest one in each direction. None of it really matters other than talking trash with the other fast guys.
Again back to our rally we took readings from two readings in each direction and gave an average of the fastest one in each direction. None of it really matters other than talking trash with the other fast guys.
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RE: are we interested in air speed or ground speed ? Does it matter
ORIGINAL: vicman
It's all about bragging rights [8D]
Again back to our rally we took readings from two readings in each direction and gave an average of the fastest one in each direction. None of it really matters other than talking trash with the other fast guys.
It's all about bragging rights [8D]
Again back to our rally we took readings from two readings in each direction and gave an average of the fastest one in each direction. None of it really matters other than talking trash with the other fast guys.
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RE: are we interested in air speed or ground speed ? Does it matter
In Wyoming and S. Dakota the downwind leg is faster no matter what your doing.
GAWD this place sucks sometimes!! lol
GAWD this place sucks sometimes!! lol
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RE: are we interested in air speed or ground speed ? Does it matter
ORIGINAL: mk1spitfire
Are doppler checkers airspeed only?
Are doppler checkers airspeed only?
#14
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RE: are we interested in air speed or ground speed ? Does it matter
What a great thread... This question comes up fairly often in different forms. The most common form is the, "my Patriot/OS .55 goes 180mph and I've got radar to prove it", thread. That turns into
"well... maybe... down hill... at 6,000ft... with a 30mph tail wind". This usually ends with "yes you have 180 on a radar gun, but no, you are not really doing 180 with an OS .55". The obvious crux of the question is, do you mean ground or airspeed?
For me, when these discussions come up (for bragging rights), you need to look at the average of two, level, passes in opposite directions. Without this I could launch an LT-40 in a hurricane and, for at least for a short period of time, claim I had a 200mph trainer with an OS LA .40 and I've got radar to prove it!
Bill
"well... maybe... down hill... at 6,000ft... with a 30mph tail wind". This usually ends with "yes you have 180 on a radar gun, but no, you are not really doing 180 with an OS .55". The obvious crux of the question is, do you mean ground or airspeed?
For me, when these discussions come up (for bragging rights), you need to look at the average of two, level, passes in opposite directions. Without this I could launch an LT-40 in a hurricane and, for at least for a short period of time, claim I had a 200mph trainer with an OS LA .40 and I've got radar to prove it!
Bill
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RE: are we interested in air speed or ground speed ? Does it matter
Bill,
Thats what we did with the speed rally we held last year. We had two passes in each direction and took the average of the two fastest.
The thing that really struck me was how the pylon racing planes had the same speed within say 4-5 mph in both directions. The next thing that I found interesting was the tremendous drop in speed from the hotliners. They would blow by the first time with incredible speed but after that they would drop 20+ mph with every pass. I expected some drop but not that much.
If you are interested we logged the speeds, model type, and power system on our website for people wanting to see what did well.
http://www.caldwellaeromodelers.com/...dSheet2008.pdf
You will notice we had a wide variety of planes show up. It really was a fun event.
Thats what we did with the speed rally we held last year. We had two passes in each direction and took the average of the two fastest.
The thing that really struck me was how the pylon racing planes had the same speed within say 4-5 mph in both directions. The next thing that I found interesting was the tremendous drop in speed from the hotliners. They would blow by the first time with incredible speed but after that they would drop 20+ mph with every pass. I expected some drop but not that much.
If you are interested we logged the speeds, model type, and power system on our website for people wanting to see what did well.
http://www.caldwellaeromodelers.com/...dSheet2008.pdf
You will notice we had a wide variety of planes show up. It really was a fun event.
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RE: are we interested in air speed or ground speed ? Does it matter
I enjoy watching the entire flight. When I see the plane at X speed unload to V max in the dive, I enjoy that portion of the flight as much as I do watching the plane gradually lose momentum during the level pass, then I get a kick out of watching it climb to do a return pass. I also like knowing what all the speeds involved were, in a dive and on the flat. If by chance my plane hits 180 in a dive, then I enjoy knowing that...and no one is going to tell me any different or how I should go about enjoying myself. I especially love watching the downwind passes, it's like Mother Nature has hit the nitrous button for me.
For those who think they deserve a Medal of Honor for only acknowledging the level speed in calm air, have at it...but don't try to tell me how I should play with my toys.
For those who think they deserve a Medal of Honor for only acknowledging the level speed in calm air, have at it...but don't try to tell me how I should play with my toys.
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RE: are we interested in air speed or ground speed ? Does it matter
ORIGINAL: combatpigg
...but don't try to tell me how I should play with my toys.
...but don't try to tell me how I should play with my toys.
#18
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RE: are we interested in air speed or ground speed ? Does it matter
Bragging rights to what? The North American piston / prop driven speed record? What is that record BTW and who has bragging rights to it?
Everyone else is either in 2nd place or worse and has a lot of catching up to do.....
the record on this continent is probably held by a FAI pylon racer.
Everyone else is either in 2nd place or worse and has a lot of catching up to do.....
the record on this continent is probably held by a FAI pylon racer.
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RE: are we interested in air speed or ground speed ? Does it matter
ORIGINAL: combatpigg
Bragging rights to what? ...
Bragging rights to what? ...
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RE: are we interested in air speed or ground speed ? Does it matter
ORIGINAL: mk1spitfire
.............That ground speed is surley the refection how fast you model feels.?
.............That ground speed is surley the refection how fast you model feels.?
to me the plane has more 'feel' when going into the wind, flying in 30-35 knot winds the down wind leg is considerably smoother and groves right along, with the head wind it's bumpy and more pitchy. as far as speed i go by indicated air speed (JetCat sensor) as the plane could care less about ground speed, stall speed is determined by allot of factors with ground speed NOT being one of them.
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RE: are we interested in air speed or ground speed ? Does it matter
Mike, someone else pointed out that a .40 sized trainer could go 200 in a tornado. I say, what's wrong with that? If I was witness to a plane that was under my control going 200 and was able to "take it all in", I would get a kick out of knowing that it did 200. I would tell the World [and I doubt that this trick has ever been done].
When a DSer is radared at the bottom of a dive, does his speed "count"? It does to him and that is all that matters. It is just a matter of degree how far you want to take the "unassisted" part of the equation for what you think counts. Maybe the only recognized clockings should be with no dive what-so-ever, just level passes? Set the ceiling at 50 feet and clock the plane in a 665 foot stretch in zero wind only [none of that 2 way average BS for me].
This forum isn't really about extreme speed, never has been. The only extreme speed guys [except for ILJ] have been run out of here for being too hardcore. If a guy wants to come here and claim 200, share his set up, talk about how it was clocked, etc., I'm all for it, it's not meaningless to me.
If a guy wants to come here and talk about a RC garbage can lid that he clocked at 200, I'll read about that with some interest, too.
I don't think any of it is worthless or meaningless, all the claims have some relative value. I come here to learn and to be entertained and the claims are just numbers...no matter where they come from.
When a DSer is radared at the bottom of a dive, does his speed "count"? It does to him and that is all that matters. It is just a matter of degree how far you want to take the "unassisted" part of the equation for what you think counts. Maybe the only recognized clockings should be with no dive what-so-ever, just level passes? Set the ceiling at 50 feet and clock the plane in a 665 foot stretch in zero wind only [none of that 2 way average BS for me].
This forum isn't really about extreme speed, never has been. The only extreme speed guys [except for ILJ] have been run out of here for being too hardcore. If a guy wants to come here and claim 200, share his set up, talk about how it was clocked, etc., I'm all for it, it's not meaningless to me.
If a guy wants to come here and talk about a RC garbage can lid that he clocked at 200, I'll read about that with some interest, too.
I don't think any of it is worthless or meaningless, all the claims have some relative value. I come here to learn and to be entertained and the claims are just numbers...no matter where they come from.