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One shot how high Altitude, Temporary O2 in RV-8

donaziza

Well Known Member
Wonder if anyone out there could help me on this. I know there have been plenty of threads on installing oxygen in an RV 8 here, but I would like to see how high I can get my plane just once just to see how high it will actually go. I started looking around to see about renting O2 equipment, and yeah, you "can" rent it, but only with those cannulas thingy's you put in your nose. I've read here on VAF those are OK at 15000', but not higher and I would be afraid to go higher with them. I do have a full face military oxygen mask, but of course it won't attach to any of those medical oxygen rentals.:mad: Any ideas??:confused:
 
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Ask some of your mates....someone will have one. I suggest that you will get to 18000 and above so you will need a mask not a canula.

Make sure you are plumbed with a spare mask, most have two ports at least. You will not last long in the 20's without O2.

Make sure you have an oximeter on all the time above 18k and monitor it as much as your altimeter :)

Be aware that thermal changes may affect the canopy/windscreen joints. People have lost windows before :eek: at FL270 in a twin turbo IO540 RV10.

Take lots of pictures and post them here :)
 
Some paradoxes here

You can certainly safely use a canula to a little above 18,000. I use one in my sailplane routinely to 18,000.

But, can you fly above 18,000 anyway? There is virtually no doubt that your -8 can make it above 18,000. So if you actually want to find out how high it will go, you will need either an IFR flight plan and equipment, or a VFR waver.
In sailplanes, we have letters of agreement that make certain defined areas available for VFR waver, and a procedure for getting approval/clearance to use it.
Absent that, how are you going to get there?
 
Now RV10inOZ has got me scared. I'm guessing the airplane "might" get to 20 or 24000, but do I have to worry about the canopy maybe shattering from cold?:eek:
 
You can certainly safely use a canula to a little above 18,000. I use one in my sailplane routinely to 18,000.

But, can you fly above 18,000 anyway? There is virtually no doubt that your -8 can make it above 18,000. So if you actually want to find out how high it will go, you will need either an IFR flight plan and equipment, or a VFR waver.
In sailplanes, we have letters of agreement that make certain defined areas available for VFR waver, and a procedure for getting approval/clearance to use it.
Absent that, how are you going to get there?

Well, I thought I could tell ATC what I want to do, and if they can accept me, and simply go where they want me to go, Im in. ( I'm intrument qualified)
 
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Walk around?

If you have a military mask and helmet, do you still have any hi friends in low places that could loan you a walk-around bottle from a compatible aircraft?

Paul

Tell me more. What is a walk around? I have a nice helmet with mask. It has been used in an L-39 and the audio is good. I don't think the O2 was used. What is the program for using these helmets with a portable bottle?

Sidenote: We bought the helmet from an "old guy" at our local radio control swap and shop. He said he used to wear it flying fish in a B-25. It is like new and does not smell like fish :p
 
Flight Levels

Don:

I was just on Weathermeister.com and it looked like the freezing level around Atlanta was in the 13-15,000 msl. range. Extrapolate that to FL220 which you might get in your plane, and I don't think your canopy will be any colder than the guys flying at 7-8,000ft. in the Northern Tier States and Canada.
 
Don:
Extrapolate that to FL220 which you might get in your plane, and I don't think your canopy will be any colder than the guys flying at 7-8,000ft. in the Northern Tier States and Canada.

Its not the temperature that is the problem, but the change in temp. If you take off and its 75 or 80, then level off at 10 degrees, then you get loud pops and a big crack in the canopy :eek:
 
Tell me more. What is a walk around? I have a nice helmet with mask. It has been used in an L-39 and the audio is good. I don't think the O2 was used. What is the program for using these helmets with a portable bottle?

Sidenote: We bought the helmet from an "old guy" at our local radio control swap and shop. He said he used to wear it flying fish in a B-25. It is like new and does not smell like fish :p

This would be an example of a walk-around bottle.

100330-F-6286F-011.jpg


You just plug a hose from your mask into one of these and turn it on. We used these in the AF. They are primarily found on larger crewed aircraft, hence the "walk-around" name.
 
Well, I thought I could tell ATC what I want to do, and if they can accept me, and simply go where they want me to go, Im in. ( I'm intrument qualified)

If you are "rated and equipped" and have the proper O2 system it is a non-issue, just pick a place clear of airways to keep it simple for the controller and request a block altitude. I have "been there and done that," I gave up at FL210, as it was very cold and not fun. Our short winged RVs really aren't happy at those altitudes. As a test pilot friend once said, "A little like balancing a bowling ball on a knitting needle". :eek:

John Clark ATP, CFI
FAAST Team Representative
EAA Flight Advisor
RV8 N18U "Sunshine"
KSBA
 
If you are "rated and equipped" and have the proper O2 system it is a non-issue, just pick a place clear of airways to keep it simple for the controller and request a block altitude. I have "been there and done that," I gave up at FL210, as it was very cold and not fun. Our short winged RVs really aren't happy at those altitudes. As a test pilot friend once said, "A little like balancing a bowling ball on a knitting needle". :eek:

Excatly what I did, with similar results. Fun to do...for awhile!
 
Guys,

I had to chime in on this one. I completely understand the excitement and gratification in exploring the performance of your home built airplane. But I don't see the point in trying to play Wiley Post in a RV.

These are spectacular performing, fun airplanes. Why jeopardize that by trying to take them somewhere they really are not meant to go? High altitude is no where to play around and there are not a lot of "good" ways to get back down quickly either.

Have fun and fly safe.

Mark
 
Guys,

I had to chime in on this one. I completely understand the excitement and gratification in exploring the performance of your home built airplane. But I don't see the point in trying to play Wiley Post in a RV.

These are spectacular performing, fun airplanes. Why jeopardize that by trying to take them somewhere they really are not meant to go? High altitude is no where to play around and there are not a lot of "good" ways to get back down quickly either.

Have fun and fly safe.

Mark

+1

If you must do it though to satisfy the inner adventurer, do it right with a new and proper O2 system.

Second hand military gear is dangerous. Remember, it's built by the lowest bidder and our gear is inspected regularly and often by pros. If it fails so much as a leak check they toss it and we get new stuff. Guess where that discarded gear sometimes winds up?

Make sure you have an out too, chopping the throttle and stuffing the nose if you have to come down fast is a great way to not only shock cool the engine, but blow right through Vne.
 
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High Altitude Stuff...

Also...it may have been mentioned here before...if you plan to go over FL240 there are some regulatory issues you have to address; and I understand the FAA aerospace medical folks at Ok City still provide high-altitude training. Military used to do it for civilian pilots, but they stopped. I believe the FAA training is free, but you have to schedule it.

Someone set me straight if I'm mis-remembering, but since my other computer got the blue screen of death, my memory is sort of hamstrung.
 
Also...it may have been mentioned here before...if you plan to go over FL240 there are some regulatory issues you have to address; and I understand the FAA aerospace medical folks at Ok City still provide high-altitude training. Military used to do it for civilian pilots, but they stopped. I believe the FAA training is free, but you have to schedule it.

Someone set me straight if I'm mis-remembering, but since my other computer got the blue screen of death, my memory is sort of hamstrung.

FAR 61.31(g) covers the training requirements for operating over 25000 feet. Altitude chamber training isn't required, but I recommend it to anyone that flies. Experiencing hypoxia is a real education.

John Clark ATP, CFI
FAAST Team Representative
EAA Flight Advisor
RV8 N18U "Sunshine"
KSBA
 
You don't have to actually go there to figure out how high you can get.

Pick your highest mission resprenstable cross-country alitude you might expect to fly such as 14,500ft MSL.

Climb at Vy recording your power and ROC to that alititude. You can reasonably extrapolate your absolute ceiling (O climb rate) and service ceilingt (100 FMP climb) from this data.

Its not perfect but close enough without having to jump through all those O2 and regulatory hoops and worries about canopies, high altitude engine fires, and Vne.

.02
 
... I would like to see how high I can get my plane just once just to see how high it will actually go. ...:

Someone has done this a few years ago. It was an RV8, IIRC. He did it in Ontario Canada. He has documented the planning and preparation in his website (quite extensive, including discussions with ATC). Unfortunately I can't find the website anymore. Maybe someone in Canada can help.
 
FAR 61.31(g) covers the training requirements for operating over 25000 feet. Altitude chamber training isn't required, but I recommend it to anyone that flies. Experiencing hypoxia is a real education.

John Clark ATP, CFI
FAAST Team Representative
EAA Flight Advisor
RV8 N18U "Sunshine"
KSBA

The learning curve on that one is kinda steep...
 
Hypoxia

As a civilian pilot, I did all day altitude chamber training at Edwards AFB in the early 90's, so been there done that. One person lost all mental capacity. Instructor YELLED at the guy, in his face, to put his mask on, but no response. Started into muscle twitching, had to input his mask on for him. Within 10 sec he was completely "back". He said he didn't hear or remember any of what happened. It was like the lights were on but no one home. Fascinating experience. Gave me incredible respect for the dangers of high altitude operations, which is the point of the training. I highly recommend anyone planning to spend any time flying over 12K ft to seek out this training.
 
As a civilian pilot, I did all day altitude chamber training at Edwards AFB in the early 90's, so been there done that. One person lost all mental capacity. Instructor YELLED at the guy, in his face, to put his mask on, but no response. Started into muscle twitching, had to input his mask on for him. Within 10 sec he was completely "back". He said he didn't hear or remember any of what happened. It was like the lights were on but no one home. Fascinating experience. Gave me incredible respect for the dangers of high altitude operations, which is the point of the training. I highly recommend anyone planning to spend any time flying over 12K ft to seek out this training.


The scarey thing is 12K is just the legal line in the sand. It varies from person to person. I can site accidents in which pilots lost consciousness at or below 12K and rode the plane to the crash scene.

When I did the altitude chamber about 10 years ago, one of the "rides" we did was at night (lights off) at 10K feet cabin altitude. There was a small red flood light on the ceiling for vis. They had us just hang out, chat, look at color charts in the red light... basic stuff for about 15-20 minutes. I didn't feel anything at all. Then they had us put our masks back on, and on the third breath it was like someone flipped on the lights. Instantly the room was so bright I could see everything. The instructors hadn't done a thing. Scared the **** out of me as I had been routinely flying in the mid-low teens at night, single pilot for a few years prior.
 
I'll chime in with the minority on this one, Don. Do your homework, carefully prepare your equipment, make a plan, and... HAVE A GREAT FLIGHT!

Although what you are considering is perfectly within the capabilities of your aircraft and with the proper preparation, you and the equipment available to you as well, I salute your enterprise (and in the face of all this negativity), your daring.

You don't get any Air Medals sitting in the 'Ready Room'.


Lee...
 
You don't get any Air Medals sitting in the 'Ready Room'.

Lee...

I agree. I've flown mine over the Sierras twice---16,500ft going West and 17,500ft coming back East. Used the cannulas as I didn't plan on going over 17,500.

Of course, I had a Pulse/Oximeter and regularly checked myself and my wife.

Let me tell you, the top of Mt. Whitney and surrounding peaks look like they're just below your toes even at 17,500!
 
I'll chime in with the minority on this one, Don. Do your homework, carefully prepare your equipment, make a plan, and... HAVE A GREAT FLIGHT!

Although what you are considering is perfectly within the capabilities of your aircraft and with the proper preparation, you and the equipment available to you as well, I salute your enterprise (and in the face of all this negativity), your daring.

You don't get any Air Medals sitting in the 'Ready Room'.


Lee...

Got all the air medals I need in Vietnam.:eek: Did my high altitude chamber training in the military.:)
 
Exxon Tiger

I'm surprised nobody's mentioned this.

Of course that's taking it to extremes. At least it doesn't get any colder once you get to the tropopause.

The bar's been set quite high - at least it was an 'RV".
 
I have had my RV7a to FL200 a few times.
It's running a 180HP engine and the plane is still climbing at 400fpm at that height with just me on board.

I won't go above that height in case my O2 decides to stop working.
 
Guys,

I had to chime in on this one. I completely understand the excitement and gratification in exploring the performance of your home built airplane. But I don't see the point in trying to play Wiley Post in a RV.

These are spectacular performing, fun airplanes. Why jeopardize that by trying to take them somewhere they really are not meant to go? High altitude is no where to play around and there are not a lot of "good" ways to get back down quickly either.

Have fun and fly safe.

Mark


Getting down fast: spins are safe and fast? Couple thousand feet per minute and no risk of bending the airplane.

Oxygen masks and pulse oximetry are easy to come by.

http://www.amazon.com/HCS4600H-Medline-OXYGEN-CONCENTRATION-ADULT/dp/B000TQET9S

http://www.amazon.com/Contec-CMS50L-Fingertip-Pulse-Oximeter/dp/B002BUYSDC

Placing the nasal canula in your mouth, close lips, and breathing through your nose will work fine for a one off flight too. Your mouth, oral pharynx, nasal pharynx, and hypo pharynx act as a large O2 reservoir. Flame on if you like, respiratory physiology is kind of my thing though.:D

I wouldn't do this flight without a pulse ox regardless of Oxygen delivery method.

Plan it right, do it smart, come back and report your findings. This type of flight is on my to do list as soon as I find a fill source for my new O2 bottle.
 
Getting down fast: spins are safe and fast? Couple thousand feet per minute and no risk of bending the airplane.

Oxygen masks and pulse oximetry are easy to come by.

http://www.amazon.com/HCS4600H-Medline-OXYGEN-CONCENTRATION-ADULT/dp/B000TQET9S

http://www.amazon.com/Contec-CMS50L-Fingertip-Pulse-Oximeter/dp/B002BUYSDC

Placing the nasal canula in your mouth, close lips, and breathing through your nose will work fine for a one off flight too. Your mouth, oral pharynx, nasal pharynx, and hypo pharynx act as a large O2 reservoir. Flame on if you like, respiratory physiology is kind of my thing though.:D

I wouldn't do this flight without a pulse ox regardless of Oxygen delivery method.

Plan it right, do it smart, come back and report your findings. This type of flight is on my to do list as soon as I find a fill source for my new O2 bottle.

OK, If you're up in IF&R territory, how do you talk to ATC with the canula in your mouth?:confused:
 
I have an oxygen system in my 8 that isn't being used.

I have flown gliders over 28000' and never worried about cracking the canopy. It was -30 at that altitude most times.
 
If you can fly a plane, this modest challenge ought not be too daunting. If its a challenge you don't care to take I provided a link to a mask too. I brought it up as an option that can be used in a pinch if youre caught without a mask some day or perhaps for one brief flight above normal cannula altitudes.

Keep in mind this is serious stuff though

http://en.wikipedia.org/wiki/Time_of_useful_consciousness

Grant, I looked at this TUC table you showed. I and my classmates did the high altitude chamber when I was in the military. Best I recall, you have only " 20 to 30 seconds" of useful consciousness above 18000', NOT 20 to30 minutes as it says here!!!!!!! And we were all in our early 20ties. I wouldn't trust this chart for a minute. Please do not try this. Have a full face mask.
 
High altitude test flight!

Hello guys,

Re-opening this thread! I just had to find out how high my RV-9A will fly! It is equiped with an OX-320 and CS prop.

It took two attemps before I was allowed to go "all the way". I tried it in Belgium first, although ATC said (over the phone) that for testing purposes they would allow me to climb to FL240, ones airborne on the day of the event, they would not let me go higher than FL195 (max VFR Alt. in Belgium).

So I tried it again in The Netherlands. The Dutch military were a lot more cooperative. I guess they never thought I would get this high!
On the agreed day, I took off from my home base and started climbing in the direction of the Netherlands, while getting approval from "Brussels Info" to contact "Dutch Mil". It is only a few minutes from my base to the Dutch border.

Dutch Mil gave me two points in their Military D-Class airspace, I was supposed to to fly between. My RV-9A was climbing like a homesick angel and when I reached the northern turn-point I still had a lot of climb potention left. When I made the 180? turn, the Trutrak was throwing from left to right, so I went back to hand flying. It turned out that I was actually flying backward, doing something like 100 KTAS and with headwinds exeeding 99 KTS (Dynon EFIS only showing 2 digits of wind velocity), which caused teh AP to oscilate left/right.

Although I was drifting close to the Amsterdam TMA, Dutch Mil let me climb further, till I had to call it a day at: 26.640 ft !!!! when there was just no more potential for climb left. The outside temparture was -30?C, with the canopy freezing over in some area's, on the inside!

This was an adventure I was dreaming about and had to get "out of my system". The oxi bottle I borrowed from the local Drugstore was EUR 2,49 for the fillng, the canula I had to buy for EUR 3,00.

Regards, Tonny.
 
Grant, I looked at this TUC table you showed. I and my classmates did the high altitude chamber when I was in the military. Best I recall, you have only " 20 to 30 seconds" of useful consciousness above 18000', NOT 20 to30 minutes as it says here!!!!!!! And we were all in our early 20ties. I wouldn't trust this chart for a minute. Please do not try this. Have a full face mask.

20 to 30 minutes is correct at 18K. You are down to 20 or 30 seconds only in a explosive decompression at altitudes above 35K. We took are masks off in the chamber at 24,000 feet and would perform a variety of tasks. Performance would start to go down hill fast after about 2 minutes at that altitude. Here are the standard tables. TUC in these tables means your ability to reasonable perform a task not when you actually pass out.

The table below reflects various altitudes with the corresponding average TUC:[4]
Altitude in Flight level Time of Useful Consciousness Altitude in meters Altitude in feet
FL 150 30 min or more 4,572 m 15,000
FL 180 20 to 30 min 5,486 m 18,000
FL 220 5-10 min 6,705 m 22,000
FL 250 3 to 6 min 7,620 m 25,000
FL 280 2.5 to 3 mins 8,534 m 28,000
FL 300 1 to 3 mins 9,144 m 30,000
FL 350 30 sec to 60 sec 10,668 m 35,000
FL 400 15 to 20 sec 12,192 m 40,000
FL 430 9 to 15 sec 13,106 m 43,000
FL 500 and above 6 to 9 sec 15,240 m 50,000
 
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