Today's Message Index:
----------------------
1. 07:39 AM - Re: Best glide speed RV6A (Doug Gray)
2. 08:19 AM - Re: Best glide speed RV6A (Dave Gmail)
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| Subject: | Re: Best glide speed RV6A |
Skylor,
Yes that is as I recall, I think the best glide angle speed corresponds to t
he tangent intercept drawn from the origin on the ROD plot. I will need to c
heck my books to confirm.
I need to figure out the best way to test these. Also I don't think I could h
ave flown my aircraft anywhere near smoothly enough during phase 1 to have c
ollected useful data.
Thanks,
Doug
Sent from my iPhone
> On 22 May 2015, at 1:31 pm, Skylor Piper <skylor4@yahoo.com> wrote:
>
> "Best glide" usually refers to best glide angle, i.e. the speed at which t
he aircraft will cover the most distance for a given amount of altitude loss
in still air. In engine out situations, this is usually what we're interes
ted in because we want to go the most distance possible with the amount of a
ltitude that we have. I believe best glide angle typically coincides with t
he speed at which L/D is the greatest in still air.
>
> Best endurance is the speed at which the rate of descent is minimum. This
is useful for getting the most time possible for troubleshooting, but not n
ecessarily traveling the greatest distance. Best endurance can occur at a s
ignificantly lower airspeed than best angle, so while the rate of descent ma
y be minimized, less forward progress is made per unit time resulting in a s
teeper glide angle.
>
> Skylor
>
> Sent from my iPhone.
>
>> On May 21, 2015, at 6:54 PM, Doug Gray <dgra1233@bigpond.net.au> wrote:
>>
>> When discussing best glide I am never sure if we are talking about best g
lide endurance or best glide range. Which do we use?
>> I have never tested these on my RV-6 but intend to do so now the engine h
as a couple of hundred hours. If someone can point me to a recommended proce
dure this would be helpful too.
>> Doug Gray
>>
>> Sent from my iPad
>>
>>> On 21 May 2015, at 9:18 am, Denis Walsh <denis.walsh@comcast.net> wrote:
>>>
>>> Charlie, I have a 6A, and I agree with your ball park figure; however I
would caution there are many variables: prop (cs or fixed), power status (s
topped prop or windmill), airplane weight, Idle rpm of your engine, etc. Th
ere are probably more.
>>>
>>> In my case I have an average weight 180hp with c/s prop and low idle spe
ed. I use 80 to 90 knots for glide and across the fence 75K. That leaves a
lot of speed to kill in the flare but I have a low idle speed and lots of d
rag if windmilling. This is what I practice with. It gives a rather steep g
lide and I am sure it would be quite different with a stopped prop or parti
al power, but I feel these would make for a better glide which I could deal w
ith. I always practice with the prop in max RPM so I have max drag.
>>>
>>> One can practice for the zero thrust, min drag glide if you fiddle with
the throttle to establish zero thrust, but I consider this to be too tough f
or me and of minimal value in an emergency which will almost certainly be di
fferent than you practiced any way! My opinion is the same about practicing
with coarse pitch glides. I don=99t think you can count on having en
ough oil pressure to go coarse pitch in many engine failure scenarios. So I
just practice the worst case, with low pitch low rpm, and glide at 80-90, u
ntil the field is made then flare, add drag and land. I figure if my emerge
ncy has better glide angle than I have practiced, I can put the flaps down s
ooner or side slip. Coming up short on final is, on the other hand usually n
ot a good option.
>>>
>>> I certainly don=99t claim this is the best or the only way to prac
tice, it=99 s just the way I do it, as you asked, based on a lot of pr
actice over the past 18 years and 3100 hours in the 6A. You would have thou
ght i would have worn it out by now but it is still going strong..
>>>
>>> I hope your shoulder heals soon.
>>>
>>>
>>> Denis Walsh
>>> denis.walsh@comcast.net
>>>
>>>
>>>
>>>> On 20May, 2015, at 11:07, <cheathco@cox.net> <cheathco@cox.net> wrote:
>>>>
>>>> Interesting article in Flying mag (may) re dead stick landings. I expe
rimented with determining that quite bit when I first got my 6A, based at L
ZU at the time. That was in late 04/early 05. I never felt I could absolutl
y put a number on it, but settled on 75/80 mph, pretty much speed on final.
This article got me thinking about it again, but due to very recent rt shou
lder surg, I will no be flying for a while. ( think I could manage everythin
g exept flaps but getting in and especially back out may take a while). Anyw
ay, would like to hear from 6A drivers what they would use for dead stick ai
r speed? Charlie H
>>>>
>>>>
>>>>
>>>> This email has been checked for viruses by Avast antivirus software.
>>>> www.avast.com
>>>>
>>>>
>>>>
>>>>
>>>> class="">http://www.matronics.com/Navigator?RV-List
>>>> class="">http://forums.matronics.com
>>>> class="">http://www.matronics.com/contribution
>>>>
>>>
>>>
>>>
>>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
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D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>>> st"">http://www.matronics.com/Navigator?RV-List
>>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3
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>>> //forums.matronics.com
>>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3
D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>>> ot;">http://www.matronics.com/contribution
>>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3
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>>>
>>
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>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
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D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>> st"">http://www.matronics.com/Navigator?RV-List
>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3
D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>> //forums.matronics.com
>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3
D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>> ot;">http://www.matronics.com/contribution
>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
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>>
>
>
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>
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| Subject: | Re: Best glide speed RV6A |
Hi Charlie,
Look up CAFE foundation, they did a full review of the RV6 6A back in 1993.
Regards
Dave Burnham
> On May 22, 2015, at 9:15 AM, Doug Gray <dgra1233@bigpond.net.au> wrote:
>
> Skylor,
> Yes that is as I recall, I think the best glide angle speed corresponds to
the tangent intercept drawn from the origin on the ROD plot. I will need to
check my books to confirm.
> I need to figure out the best way to test these. Also I don't think I coul
d have flown my aircraft anywhere near smoothly enough during phase 1 to hav
e collected useful data.
> Thanks,
> Doug
>
> Sent from my iPhone
>
>> On 22 May 2015, at 1:31 pm, Skylor Piper <skylor4@yahoo.com> wrote:
>>
>> "Best glide" usually refers to best glide angle, i.e. the speed at which t
he aircraft will cover the most distance for a given amount of altitude loss
in still air. In engine out situations, this is usually what we're interes
ted in because we want to go the most distance possible with the amount of a
ltitude that we have. I believe best glide angle typically coincides with t
he speed at which L/D is the greatest in still air.
>>
>> Best endurance is the speed at which the rate of descent is minimum. Thi
s is useful for getting the most time possible for troubleshooting, but not n
ecessarily traveling the greatest distance. Best endurance can occur at a s
ignificantly lower airspeed than best angle, so while the rate of descent ma
y be minimized, less forward progress is made per unit time resulting in a s
teeper glide angle.
>>
>> Skylor
>>
>> Sent from my iPhone.
>>
>>> On May 21, 2015, at 6:54 PM, Doug Gray <dgra1233@bigpond.net.au> wrote:
>>>
>>> When discussing best glide I am never sure if we are talking about best g
lide endurance or best glide range. Which do we use?
>>> I have never tested these on my RV-6 but intend to do so now the engine h
as a couple of hundred hours. If someone can point me to a recommended proce
dure this would be helpful too.
>>> Doug Gray
>>>
>>> Sent from my iPad
>>>
>>>> On 21 May 2015, at 9:18 am, Denis Walsh <denis.walsh@comcast.net> wrote
:
>>>>
>>>> Charlie, I have a 6A, and I agree with your ball park figure; however I
would caution there are many variables: prop (cs or fixed), power status (s
topped prop or windmill), airplane weight, Idle rpm of your engine, etc. Th
ere are probably more.
>>>>
>>>> In my case I have an average weight 180hp with c/s prop and low idle sp
eed. I use 80 to 90 knots for glide and across the fence 75K. That leaves a
lot of speed to kill in the flare but I have a low idle speed and lots of d
rag if windmilling. This is what I practice with. It gives a rather steep g
lide and I am sure it would be quite different with a stopped prop or parti
al power, but I feel these would make for a better glide which I could deal w
ith. I always practice with the prop in max RPM so I have max drag.
>>>>
>>>> One can practice for the zero thrust, min drag glide if you fiddle wit
h the throttle to establish zero thrust, but I consider this to be too tough
for me and of minimal value in an emergency which will almost certainly be d
ifferent than you practiced any way! My opinion is the same about practicin
g with coarse pitch glides. I don=99t think you can count on having e
nough oil pressure to go coarse pitch in many engine failure scenarios. So I
just practice the worst case, with low pitch low rpm, and glide at 80-90, u
ntil the field is made then flare, add drag and land. I figure if my emerge
ncy has better glide angle than I have practiced, I can put the flaps down s
ooner or side slip. Coming up short on final is, on the other hand usually n
ot a good option.
>>>>
>>>> I certainly don=99t claim this is the best or the only way to pra
ctice, it=99 s just the way I do it, as you asked, based on a lot of p
ractice over the past 18 years and 3100 hours in the 6A. You would have tho
ught i would have worn it out by now but it is still going strong..
>>>>
>>>> I hope your shoulder heals soon.
>>>>
>>>>
>>>> Denis Walsh
>>>> denis.walsh@comcast.net
>>>>
>>>>
>>>>
>>>>> On 20May, 2015, at 11:07, <cheathco@cox.net> <cheathco@cox.net> wrote:
>>>>>
>>>>> Interesting article in Flying mag (may) re dead stick landings. I exp
erimented with determining that quite bit when I first got my 6A, based at L
ZU at the time. That was in late 04/early 05. I never felt I could absolutl
y put a number on it, but settled on 75/80 mph, pretty much speed on final.
This article got me thinking about it again, but due to very recent rt shou
lder surg, I will no be flying for a while. ( think I could manage everythin
g exept flaps but getting in and especially back out may take a while). Anyw
ay, would like to hear from 6A drivers what they would use for dead stick ai
r speed? Charlie H
>>>>>
>>>>>
>>>>>
>>>>> This email has been checked for viruses by Avast antivirus software.
>>>>> www.avast.com
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> class="">http://www.matronics.com/Navigator?RV-List
>>>>> class="">http://forums.matronics.com
>>>>> class="">http://www.matronics.com/contribution
>>>>>
>>>>
>>>>
>>>>
>>>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
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>>>> st"">http://www.matronics.com/Navigator?RV-List
>>>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
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>>>> //forums.matronics.com
>>>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
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>>>> ot;">http://www.matronics.com/contribution
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>>>>
>>>
>>>
>>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
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D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>>> st"">http://www.matronics.com/Navigator?RV-List
>>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3
D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>>> //forums.matronics.com
>>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3
D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>>> ot;">http://www.matronics.com/contribution
>>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
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>>
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>> st"">http://www.matronics.com/Navigator?RV-List
>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
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>> //forums.matronics.com
>> D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
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D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>> ot;">http://www.matronics.com/contribution
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>
>
>
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>
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