TomVal

TomVal

Well Known Member
After 15 months of down time to complete service bulletins and additional mods, our RV8 is about ready to once again take to the skies. I am seeking information in the following areas:

Best Glide Speed
Emergency Procedures Section of POH
Aerobatic Maneuver Entry Speeds

The existing POH that came with the aircraft did not have these sections of the POH completed. The aerobatic envelope also had not been opened.

Best Glide Speed:
In have a Cato, fixed pitch, 3 bladed prop. I am looking for a target speed to give me a reference for my initial flight testing of that parameter.

Emergency Procedures:
I have been writing my own and have also reviewed EP formats on the VAF website, although none of the formats listed specifically included the RV8.

Aerobatic Envelope:
I called the local FSDO and inquired about me, being the non-builder, opening the aerobatic envelope. I will in fact be able to open the envelope as long as I comply with the airspace restrictions for flight testing. I would be interested in target entry speeds and ?G? loading for the typical family of aerobatic maneuvers.

Regards,
 
We state before each takeoff, to use "80K, min 75K with Flap" in case of engine failure...

I am not sure if that is the optimum (it will vary of course with weight)... but be wary in the RV series, especially with a draggy prop (e.g. C/S) of "getting slow". The short stubby wings build up drag quickly as you get slow and then sort of "drop out of the sky" :eek: Hence the minimum speeds we use above for the final approach to give us the ability to flare and land.

I cannot think of any Emergency Procedures "specific" to the RV-8 as an aircraft. General light aircraft principles hold, and details will depend on engine type / installation etc.

Aeros... The speeds in the Builder's manual give quite a range - you can get round on the lower end, but it's all a bit easier if you go a bit faster. It gives Loops as 140-190mph (120-165K) - which is a good range for most things. A note on Snap Rolls not being ideally suited to RVs, but recommends 80-110mph.

You will not need more than ~3g for most entries. As with the glide above, pull more and those wings will just create lots of drag!

if you are not familiar with the RV for aerobatics, take it easy early on ;) Specific points:
  1. RV-8 Va is stated as 142mph = 123K - well below what you would enter most aerobatics at. It is quite possible therefore, and has been done, to simply tear the wings off with unfortunate consequences :(
  2. The RV-8 will behave very differently Dual and Solo.. and is quite easy to get aft of the Aerobatic CG limit dual (depending on basic CG). If you get an aft CG, stick forces get lighter and Point 1 above becomes even easier. For solo aeros, and to make life easier on my arm, I now carry 50lbs+ of ballast in the rear baggage area (suitably secured of course).
  3. It will build up speed very quickly with the nose down - it will go through Vne easily, and with a FP prop easily overspeed the engine. Get some 'g' on early on the down part of each manoeuvre. Consider eastablishing the throttle position for Max RPM near VNE, then slow to say 130K, and check RPM. Now if you set that RPM at 130K prior doing aerobatics, you should have protection against overspeeding, and hopefully find it enough power
  4. It Stall Turns beautifully if you put the rudder on just below 40K - either way, and leave the power on. But I am not sure what a Stall Turn is called in the USA :confused:
Andy & Ellie Hill
RV-8 G-HILZ
 
Andy Hill said:
We state before each takeoff, to use "80K, min 75K with Flap" in case of engine failure...

I am not sure if that is the optimum (it will vary of course with weight)... but be wary in the RV series, especially with a draggy prop (e.g. C/S) of "getting slow". The short stubby wings build up drag quickly as you get slow and then sort of "drop out of the sky" :eek: Hence the minimum speeds we use above for the final approach to give us the ability to flare and land.

I cannot think of any Emergency Procedures "specific" to the RV-8 as an aircraft. General light aircraft principles hold, and details will depend on engine type / installation etc.

Aeros... The speeds in the Builder's manual give quite a range - you can get round on the lower end, but it's all a bit easier if you go a bit faster. It gives Loops as 140-190mph (120-165K) - which is a good range for most things. A note on Snap Rolls not being ideally suited to RVs, but recommends 80-110mph.

You will not need more than ~3g for most entries. As with the glide above, pull more and those wings will just create lots of drag!

if you are not familiar with the RV for aerobatics, take it easy early on ;) Specific points:
  1. RV-8 Va is stated as 142mph = 123K - well below what you would enter most aerobatics at. It is quite possible therefore, and has been done, to simply tear the wings off with unfortunate consequences :(
  2. The RV-8 will behave very differently Dual and Solo.. and is quite easy to get aft of the Aerobatic CG limit dual (depending on basic CG). If you get an aft CG, stick forces get lighter and Point 1 above becomes even easier. For solo aeros, and to make life easier on my arm, I now carry 50lbs+ of ballast in the rear baggage area (suitably secured of course).
  3. It will build up speed very quickly with the nose down - it will go through Vne easily, and with a FP prop easily overspeed the engine. Get some 'g' on early on the down part of each manoeuvre. Consider eastablishing the throttle position for Max RPM near VNE, then slow to say 130K, and check RPM. Now if you set that RPM at 130K prior doing aerobatics, you should have protection against overspeeding, and hopefully find it enough power
  4. It Stall Turns beautifully if you put the rudder on just below 40K - either way, and leave the power on. But I am not sure what a Stall Turn is called in the USA :confused:
Andy & Ellie Hill
RV-8 G-HILZ
Click to expand...


Andy,

Thanks, that helps!

Regards,
 
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