Beaver Tips
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Beaver Tips
Just started flying one as a part time gig. From my regular flying job. But have never flown one before.
Looking for some tips.
Anything would be good. Esspeacially with regards to T/O technique and flap settings, and flying her with a load.
Looking for some tips.
Anything would be good. Esspeacially with regards to T/O technique and flap settings, and flying her with a load.
- NoseDraggers Suck
Re: Beaver Tips
Turn your ailerons full deflection and match them with the flaps - ergo bingo TO flaps setting.
Make sure the oil cap is on tight.
Pick the fullest tank (should be the front).
Do a mag check and run the prop through.
Carb heat is essential - check it always.
Hot start - mags on crank and pump the throttle once twice then crack the throttle a half inch. Vroom.
Flaps up before power reduction (I always hated that).
Using primer? Make sure its locked.
NEVER use part-throttle for take-off.
NEVER check mags in flight.
Fuel pressure twitch? Switch tanks!
Get used to her before you use full flaps for landing.
Put your can of Pledge behind your seat cushion at your lumbar area to help with "Beaver Back."
An oil pressure drop that stabilizes at a lower setting means the oil screen is bypassing and she's gonna blow!
NEVER NEVER NEVER take the old gal for granted or she'll finish you off. That wrinkle in the dashboard? Somebody else' forehead who DID take her for granted.
This is fun - might still be able to drive one.....
Almost forgot - 2 good paddles, cans of oil, Pledge, axe, 100 ' rope, float pump, first aid kit, a good sharp knife on your belt (for seat belts and laces) and I'll think of more....
Make sure the oil cap is on tight.
Pick the fullest tank (should be the front).
Do a mag check and run the prop through.
Carb heat is essential - check it always.
Hot start - mags on crank and pump the throttle once twice then crack the throttle a half inch. Vroom.
Flaps up before power reduction (I always hated that).
Using primer? Make sure its locked.
NEVER use part-throttle for take-off.
NEVER check mags in flight.
Fuel pressure twitch? Switch tanks!
Get used to her before you use full flaps for landing.
Put your can of Pledge behind your seat cushion at your lumbar area to help with "Beaver Back."
An oil pressure drop that stabilizes at a lower setting means the oil screen is bypassing and she's gonna blow!
NEVER NEVER NEVER take the old gal for granted or she'll finish you off. That wrinkle in the dashboard? Somebody else' forehead who DID take her for granted.
This is fun - might still be able to drive one.....
Almost forgot - 2 good paddles, cans of oil, Pledge, axe, 100 ' rope, float pump, first aid kit, a good sharp knife on your belt (for seat belts and laces) and I'll think of more....
"What's it doing now?"
"Fly low and slow and throttle back in the turns."
"Fly low and slow and throttle back in the turns."
Re: Beaver Tips
Forgot (how could I?) get a good pfd and do the immersion course - could save your life. If you're alive you can help your passengers - your job, right?
I knew a couple of guys who flew Beavers virtually all their careers and they eventually crashed them and killed themselves. She's a great a/c and one that will never forgive, either. Don't get complacent.
Boring Old Fart.................................SWITCH OFF
I knew a couple of guys who flew Beavers virtually all their careers and they eventually crashed them and killed themselves. She's a great a/c and one that will never forgive, either. Don't get complacent.
Boring Old Fart.................................SWITCH OFF
"What's it doing now?"
"Fly low and slow and throttle back in the turns."
"Fly low and slow and throttle back in the turns."
Re: Beaver Tips
Thats some sound advice Xsbank;
Make sure the oil cap is on tight - no big deal if you forget about this one.. it'll make such a mess you'll figure it out pretty quick!!
You can't stress that one enough. Full-flap is probably the most unforgiving configuration a Beaver can be in. Keep plenty of power on if you find yourself in that situation.Get used to her before you use full flaps for landing.
Make sure the oil cap is on tight - no big deal if you forget about this one.. it'll make such a mess you'll figure it out pretty quick!!
Re: Beaver Tips
Thanks Mr. North - I'm very surprised that I haven't been jumped all over for these posts - I guess most drivers are hard at it this time of year! Either that or they've all got videotron and they're all crapped out!
"What's it doing now?"
"Fly low and slow and throttle back in the turns."
"Fly low and slow and throttle back in the turns."
Re: Beaver Tips
I never pump the throttle for start up. Cold or hot. Prime only. 4 to 6 squirts cold 1or 2 warm.
Pumping the throttle increases risk of fire.
However many do pump the throttle, so make sure you only do so with the starter engaged.
I always shut off with the mags and it will then start with no prime or pumping whatever, unless you are too long between shut down and start up.
Bob
Pumping the throttle increases risk of fire.
However many do pump the throttle, so make sure you only do so with the starter engaged.
I always shut off with the mags and it will then start with no prime or pumping whatever, unless you are too long between shut down and start up.
Bob
Re: Beaver Tips
Very important: Never try a level turn exceeding 30 degrees bank without extending some flap. climb flap will do.
Without getting into exact numbers; at some bank angle exceeding 30 degrees the stall speed increases and the airspeed decreases until they are one and the same.
Because the wing is not tapered and has no washout like a Cessna, a turning stall is very abrupt if it does happen.
Bob
Without getting into exact numbers; at some bank angle exceeding 30 degrees the stall speed increases and the airspeed decreases until they are one and the same.
Because the wing is not tapered and has no washout like a Cessna, a turning stall is very abrupt if it does happen.
Bob
Re: Beaver Tips
First, every engine starts different. When they are warm you can start them by pumping the throttle, but make sure it`s turning over a few times before hitting the mags. Cross wind take off with a wind from the left, use climb flap till on the step, then take off flap once on the step.
Re: Beaver Tips
xsbank wrote:NEVER use part-throttle for take-off.
Why is this?
Re: Beaver Tips
I had the same thought. On wheels we routinely used 30 inches on take off. Sea level in the arctic and light loads. You simply dont have to run the old engine to red line to perform well. On floats, hot day, full load. You have to think differently.
I suspect that the poster is referring to float flying without thinking through the absoluteness of the statement as it applies to all Beaver flying. It is one of the dangers of giving tips. Get into the habit of only using full power for takeoff and it is easy to forget that if you transition or there are different circumsatances things might be a bit different.
Generally, I kind of liked the tips given
I suspect that the poster is referring to float flying without thinking through the absoluteness of the statement as it applies to all Beaver flying. It is one of the dangers of giving tips. Get into the habit of only using full power for takeoff and it is easy to forget that if you transition or there are different circumsatances things might be a bit different.
Generally, I kind of liked the tips given
99% of pilots give the rest a bad name
What we learn from history is that we fail to learn from history
What we learn from history is that we fail to learn from history
Re: Beaver Tips
I have been on the road for a few days with no access to a computer. I was wondering what kinda of responses I would get from this board.
It sounds like a number of you are Beaver pros, so thanks you for all the tips and keep them coming if ya think of anymore. They are Greatly appreaciated.
I like the airplane so far, she comes off the water pretty nicely, just seem that once that is over... watch out as she is no home sick angel eh.
It sounds like a number of you are Beaver pros, so thanks you for all the tips and keep them coming if ya think of anymore. They are Greatly appreaciated.
I like the airplane so far, she comes off the water pretty nicely, just seem that once that is over... watch out as she is no home sick angel eh.
- NoseDraggers Suck
Re: Beaver Tips
If you ever find you've got that sinking feeling, go for flaps before you worry about power. Flaps are paramount to the whole thing.
Always leave the selector handle in the down position.
The guys who have tried to fly them like a 185 get bit pretty hard.
A high time Beaver driver told me one time, "you don't fly a Beaver, you shepherd it around."
Always leave the selector handle in the down position.
The guys who have tried to fly them like a 185 get bit pretty hard.
A high time Beaver driver told me one time, "you don't fly a Beaver, you shepherd it around."
Last edited by HS-748 2A on Wed Jul 22, 2009 7:57 pm, edited 1 time in total.
The fastest way to turn money into smoke and noise..
Re: Beaver Tips
I've got a few questions for some of you beaver vets, Proper use of carb heat, All I know is keep it in the green. Hot days; The oil temp gets right up to redline, Ive had it there twice and its not a great feeling, is this normal on really hot days?
STOL landings with steep approaches; she builds a lot of airspeed when you nose her down, Do you use guys side slip her down? or just let her build that extra speed. Strapping 45 gal. drums in her....all the attach points are low and they like to slide down the barrel after a little while, how do some of you guys do it? thanks for the replys.
STOL landings with steep approaches; she builds a lot of airspeed when you nose her down, Do you use guys side slip her down? or just let her build that extra speed. Strapping 45 gal. drums in her....all the attach points are low and they like to slide down the barrel after a little while, how do some of you guys do it? thanks for the replys.
Re: Beaver Tips
YOU GUYS!
Using part-throttle on a radial will kill it as fast as any way I know! All of the 'extra' throttle movement and extra noise is pumping raw gas into the cylinders for cooling them to prevent detonation. This is particularly important these days as we are using low-lead fuel. The engine was designed for 80/87 gas and even on that fuel we were never allowed to use low-power for take-off. Why else would we be taking off in Full Rich? You get more power leaned out, but you burn cylinders and valves. I've seen cylinders destroyed by detonation and its ugly. Besides, when you are flying your Beav, is there any other time you want your engine to stop besides being on the ground? Don't tell me you also lean for the take--off (unless you are very high)?
Totally false economy. You are asking the engine to put out significant power with insufficient airflow for cooling. Remember the phrase "air cooled?" These engines have been around almost as long as Cat and you should not try and re-invent the ops manual.
Our engines always went 'on condition' using full take-off thrust every time.
How long are you allowed to use full rated take-off power for? What does the book say? I forget now but I'll put a Guinness on it being 5 minutes.
I'll repeat what I said and I'll stand by it - don't EVER use partial throttle for take-off!
Using part-throttle on a radial will kill it as fast as any way I know! All of the 'extra' throttle movement and extra noise is pumping raw gas into the cylinders for cooling them to prevent detonation. This is particularly important these days as we are using low-lead fuel. The engine was designed for 80/87 gas and even on that fuel we were never allowed to use low-power for take-off. Why else would we be taking off in Full Rich? You get more power leaned out, but you burn cylinders and valves. I've seen cylinders destroyed by detonation and its ugly. Besides, when you are flying your Beav, is there any other time you want your engine to stop besides being on the ground? Don't tell me you also lean for the take--off (unless you are very high)?
Totally false economy. You are asking the engine to put out significant power with insufficient airflow for cooling. Remember the phrase "air cooled?" These engines have been around almost as long as Cat and you should not try and re-invent the ops manual.
Our engines always went 'on condition' using full take-off thrust every time.
How long are you allowed to use full rated take-off power for? What does the book say? I forget now but I'll put a Guinness on it being 5 minutes.
I'll repeat what I said and I'll stand by it - don't EVER use partial throttle for take-off!
"What's it doing now?"
"Fly low and slow and throttle back in the turns."
"Fly low and slow and throttle back in the turns."
- Cat Driver
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Re: Beaver Tips
I'll repeat what I said and I'll stand by it - don't EVER use partial throttle for take-off!
The hardest thing about flying is knowing when to say no
After over a half a century of flying no one ever died because of my decision not to fly.
After over a half a century of flying no one ever died because of my decision not to fly.
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Re: Beaver Tips
XS.... I like my Guinness served slightly cooler than room temp
My ancient DeHavilland book says 1 minute at 36.5 inches and 2300RPM. Max continuous is 33.5 inches and 2200.
You seem to have a good memory & good advice about the rest though!!
Fly Safe

You seem to have a good memory & good advice about the rest though!!
Fly Safe
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Re: Beaver Tips
One caveat I think. Never use a MP more than max power for takeoff.xsbank wrote: I'll repeat what I said and I'll stand by it - don't EVER use partial throttle for take-off!
AFAIK, any engine with boost either has to have a pressure carburetor or fuel injection and meters fuel based on MP, not throttle position. So you will still get fuel cooling at partial throttle if you are at max power (limiting MP) for your particular engine.
For fancy engines with boost controllers, full throttle all the time for sure. But for ground-boosted supercharged engines and fixed-waste gate turbos, full throttle might send jugs flying off depending on what MP it is boosted up too. I've operated a few planes where full-throttle is a no-no as a result of engine limitations...
Geez did I say that....? Or just think it....?
Re: Beaver Tips
Wouldn't the extra octane number in the 100LL be more than adequate to prevent detonation on an engine designed for 80/87? That's 13-20 more octane points. You could pretty much double your compression ratio( I don't know what a stock CR on a beaver is so don't quote me on this) and still not detonate with that?xsbank wrote: The engine was designed for 80/87 gas and even on that fuel we were never allowed to use low-power for take-off. Why else would we be taking off in Full Rich? You get more power leaned out, but you burn cylinders and valves. I've seen cylinders destroyed by detonation and its ugly. Besides, when you are flying your Beav, is there any other time you want your engine to stop besides being on the ground? Don't tell me you also lean for the take--off (unless you are very high)?
Re: Beaver Tips
Thanks for the clarification, (do I call you Angry or Inch or Mr. Inch or Capt. Angry? I'm confused over the protocol) I did think, while noodling about at work, that 5 minutes would be a looooong time at TO power...
I can remember dynamite hauls to the Queen Charlottes that probably pushed those limits somewhat....
I don't have any crusty old engineers nearby who might remember what a radial engine is, but I am POSITIVE that a reduced-power take-off compromises engine cooling and detonation control.
On a R-2800, wet power was the injection of water-methanol into the intake system so that the mixture could be leaned out. This resulted in about a 300 hp gain, just because of the leaned mixture and the water mixture prevented the engine from melting. Remember that CPAir DC-6 in Prince Rupert that had a 3-going on 4-engine failure when the mechanics put wing-defrosting fluid in the water-meth tanks? I'm showing my age, somewhat.
Reduced-power take-offs are a manifestation of turbines and jet engines and have no effect on a modern turbine. You used to have to use water-meth on those old Darts, but that wore them out faster.
I might be available to pay off that Guinness in a a week or so, at the Flying Beaver - I'll let you know.
I can remember dynamite hauls to the Queen Charlottes that probably pushed those limits somewhat....
I don't have any crusty old engineers nearby who might remember what a radial engine is, but I am POSITIVE that a reduced-power take-off compromises engine cooling and detonation control.
On a R-2800, wet power was the injection of water-methanol into the intake system so that the mixture could be leaned out. This resulted in about a 300 hp gain, just because of the leaned mixture and the water mixture prevented the engine from melting. Remember that CPAir DC-6 in Prince Rupert that had a 3-going on 4-engine failure when the mechanics put wing-defrosting fluid in the water-meth tanks? I'm showing my age, somewhat.
Reduced-power take-offs are a manifestation of turbines and jet engines and have no effect on a modern turbine. You used to have to use water-meth on those old Darts, but that wore them out faster.
I might be available to pay off that Guinness in a a week or so, at the Flying Beaver - I'll let you know.
"What's it doing now?"
"Fly low and slow and throttle back in the turns."
"Fly low and slow and throttle back in the turns."
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Re: Beaver Tips
What is it that you are saying here? Detonation limits would obviously be reduced, and 100LL has 4 times more lead than 80/87, so what is so important?This is particularly important these days as we are using low-lead fuel. The engine was designed for 80/87 gas
We're all here, because we're not all there.
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Re: Beaver Tips
Reduced power yes. Reduced throttle, no. You want to make sure the extra fuel is in the engine during takeoff (power enrichment). This cools the engine and actually provides more power in spite of the overly rich mixture. This is due to the evaporative cooling of the fuel-air mixture, making it more dense. In any engine where there is a possibility of overboosting, the power enrichment valve (or whatever they use) will open before full throttle is reached to cool the engine to prevent detonation and to make takeoff power.xsbank wrote: I don't have any crusty old engineers nearby who might remember what a radial engine is, but I am POSITIVE that a reduced-power take-off compromises engine cooling and detonation control.
I don't have any flying experience on the Beaver, so I can't remember if doing full-throttle will peg the MP gauge past the red line (full throttle static run-ups during maintenance checks are kind of frowned upon). But the 1340s I worked on would overboost at full throttle.
So, full power for takeoff, all the time (piston engines). But if full-throttle exceeds engine limits, don't do it...
Geez did I say that....? Or just think it....?
Re: Beaver Tips
If you are at sea level, full throttle WILL exceed the max allowed manifold pressure. We used to call it "war emergency," your last ditch escape thrust setting if you otherwise had screwed up and needed a bit extra to save your butt. If you ever needed it, it was likely that you had screwed up royally. You had also royally compromised your engine.
I don't remember much about octane or fuel to make much of a logical argument, but my understanding is the higher the octane, the harder it is to get it to burn evenly, hence the lead that helped propagate the flame front, that the fuel itself did not supply more power but was tailored to operate in engines depending upon their compression, which did affect power.
Lower octane fuels required less lead because they were inherently better at burning in the engine, lead in lower octane fuel was only added to lubricate the valves. Lower octane fuel was less likely to detonate in a lower compression engine unless the mechanical bits were overheated and the fuel exploded (which is bad - you want it to burn) capriciously which destroys engines.
I do not know what manifold pressure opens the valve in the carburetor that dumps in the fuel for cooling, but I do know it will open if you meet full rated take-off settings.
Why does a Junior run low compression yet an 1830 or 2800 uses high compression? Depends upon what the designer intended the power-to-weight ratio to be. Perhaps, back in the dim reaches of time, the junior was designed for lower octane fuel because the supply was mostly lower octane? Maybe the Junior would really snort if she had higher compression (it was also intended to be a low-altitude engine for utility aircraft...)?
Anyway, somebody asked for tips and although I should know better, I answered...
Like they used to say around here, YMMV.
I don't remember much about octane or fuel to make much of a logical argument, but my understanding is the higher the octane, the harder it is to get it to burn evenly, hence the lead that helped propagate the flame front, that the fuel itself did not supply more power but was tailored to operate in engines depending upon their compression, which did affect power.
Lower octane fuels required less lead because they were inherently better at burning in the engine, lead in lower octane fuel was only added to lubricate the valves. Lower octane fuel was less likely to detonate in a lower compression engine unless the mechanical bits were overheated and the fuel exploded (which is bad - you want it to burn) capriciously which destroys engines.
I do not know what manifold pressure opens the valve in the carburetor that dumps in the fuel for cooling, but I do know it will open if you meet full rated take-off settings.
Why does a Junior run low compression yet an 1830 or 2800 uses high compression? Depends upon what the designer intended the power-to-weight ratio to be. Perhaps, back in the dim reaches of time, the junior was designed for lower octane fuel because the supply was mostly lower octane? Maybe the Junior would really snort if she had higher compression (it was also intended to be a low-altitude engine for utility aircraft...)?
Anyway, somebody asked for tips and although I should know better, I answered...
Like they used to say around here, YMMV.
"What's it doing now?"
"Fly low and slow and throttle back in the turns."
"Fly low and slow and throttle back in the turns."
Re: Beaver Tips
Actually a higher octane controls the burn better than low octane. With lower octane you can get detonation, pre-detonation, or even preignition becuase the fuel will ignite premature due to compression. That is why high compression engines need higher octane values.
Some engines I believe still call for lead not just for the burn characteristics, but more for the valve seat protection.
But I know nothing about beavers(the metal ones that is) so...
Some engines I believe still call for lead not just for the burn characteristics, but more for the valve seat protection.
But I know nothing about beavers(the metal ones that is) so...
Re: Beaver Tips
For take off you can put the throttle lever in any position you want as long as the manifold pressure gauge reads 36.5" maximum and governed RPM 2300 for a maximum of 1 minute.on take off. At sea level with full throttle most beaver engines will not exceed 40" MAP.Very simple. The higher the altitude the farther forward the throttle lever until at some point the throttle will be all the way forward and above that the manifold pressure will read less on take off. Somewhat above 4000 feet.
These engines are supercharged (Gear driven) but not turbo-supercharged (exhaust driven) and loose pressure with altitude, depending on the ratio of supercharger. for example 10 to 1 or 12 to 1 ratio.
The most common climb power is 2000 RPM and 30" MAP but maximum continuous power allowed is 33.5" MAP and 2200 RPM full rich mixture.
Do not lean out above 30"MAP and or 2000 RPM.
Engine gauges in the green range require full rich. Leaning allowed in blue range only.
Reduce MAP by 2% for every 11 degrees C below standard atmosphere temperature (15 degrees C.)
Regarding the carb heat question: In cruise apply and lock carb heat sufficiently enough to maintain 4 degrees C on the gauge and reset the throttle for cruise and lean. higher Carb temperature equals lower air density or put another way equals flight at a higher altitude and allows the leaning required to match the fuel consumption numbers from the manual. This is not actually required but is only an aid in obtaining book fuel consumptions. A lot of companies do not like their Beavers leaned out at all below 5000 feet. Some need to be leaned out as some carbs run quite rich.
A rule of thumb is to set cruise power and apply carb. heat until MAP drops 1/2 inch. Then reapply desired MAP and lean mixture. This rule of thumb is because the carb temp gauge is a bit hard to read on some beavers.
Be very careful with the mixture. As long as plugs are not fouling it is better to run on the rich side; especially for the inexperience pilots.
I am going to restate not to pump the throttle to prime. 4 to 6 squirts with the primer cold Summer and 1 to 3 warm and not usually required within the first 10 minutes or so after shut down with the mags. Pumping the throttle can cause back fire and carburator fire. I have seen it happen
When you prime with the throttle the fuel runs out below. When you prime with the primer you squirt the fuel directly into the top 4 cylinders, right where the spark is supposed to be when you connect the starter. The primer does not prime the other cylinders for a good reason. The fuel all runs out through the open valves.
Whew!
Bob Bates
These engines are supercharged (Gear driven) but not turbo-supercharged (exhaust driven) and loose pressure with altitude, depending on the ratio of supercharger. for example 10 to 1 or 12 to 1 ratio.
The most common climb power is 2000 RPM and 30" MAP but maximum continuous power allowed is 33.5" MAP and 2200 RPM full rich mixture.
Do not lean out above 30"MAP and or 2000 RPM.
Engine gauges in the green range require full rich. Leaning allowed in blue range only.
Reduce MAP by 2% for every 11 degrees C below standard atmosphere temperature (15 degrees C.)
Regarding the carb heat question: In cruise apply and lock carb heat sufficiently enough to maintain 4 degrees C on the gauge and reset the throttle for cruise and lean. higher Carb temperature equals lower air density or put another way equals flight at a higher altitude and allows the leaning required to match the fuel consumption numbers from the manual. This is not actually required but is only an aid in obtaining book fuel consumptions. A lot of companies do not like their Beavers leaned out at all below 5000 feet. Some need to be leaned out as some carbs run quite rich.
A rule of thumb is to set cruise power and apply carb. heat until MAP drops 1/2 inch. Then reapply desired MAP and lean mixture. This rule of thumb is because the carb temp gauge is a bit hard to read on some beavers.
Be very careful with the mixture. As long as plugs are not fouling it is better to run on the rich side; especially for the inexperience pilots.
I am going to restate not to pump the throttle to prime. 4 to 6 squirts with the primer cold Summer and 1 to 3 warm and not usually required within the first 10 minutes or so after shut down with the mags. Pumping the throttle can cause back fire and carburator fire. I have seen it happen
When you prime with the throttle the fuel runs out below. When you prime with the primer you squirt the fuel directly into the top 4 cylinders, right where the spark is supposed to be when you connect the starter. The primer does not prime the other cylinders for a good reason. The fuel all runs out through the open valves.
Whew!
Bob Bates
Last edited by beaverbob on Tue Jun 23, 2009 9:18 pm, edited 2 times in total.
Re: Beaver Tips
A2G wrote:Actually a higher octane controls the burn better than low octane. With lower octane you can get detonation, pre-detonation, or even preignition becuase the fuel will ignite premature due to compression. That is why high compression engines need higher octane values.
Some engines I believe still call for lead not just for the burn characteristics, but more for the valve seat protection.
But I know nothing about beavers(the metal ones that is) so...
You are correct although I might add that 100 low lead has 4 times as much lead as 80/87 gasoline.(2 grams lead per US gal compared to .5)
I used to mix my 100 octane with 50% to 75% unleaded car gas to equal 80/87, as per an STC.