My first time hand propping with a dead battery

mandm

mandm

Avionics Upgrade
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Michael
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Sooo on the way back from Miami, at one of my fuel (well more of a toilet break) stops, I went to start the engine and it was a hot start and I was cranking it for several seconds (15-20 seconds) and then the battery went dead (12.1 to 11.8 Volts). I was like nooooooo. Tried a couple more times to no luck. But I experienced issues with starting (bad starter that was replaced) in the past and learned how to hand prop (well sort of), so quick tutorial to "andm", hand brake on, mags on, enrichen the mixture to the "E" when its starting to catch and be prepared to hit the brakes if the airplane is going to run me over, and don't touch the handbrake.

Went out of the airplane and started to handprop, wow it takes a bit of elbow grease to do this! After a few tries, with the door still open, Kibble decides to get out of the airplane. Pause, placed Kibble inside, door closed. A few more times, I notice that the engine is starting to build pressure, and I can tell its getting ready, so I inform "andm" of this, and wah la, engine start!

Avionics ON, battery is showing as charging with positive amps. Now I'm wondering if I need a new battery, or if this was a fluke, or if I forgot to turn something off recently. We kept an eye on voltage and amps throughout the flight, after she started up, Volts returned to 13.3 Volts and ended at 13.4 Volts upon landing. I especially want this addressed if we are planning the Iceland / EU trip next month.
 
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With a 12V system, carry a lithium jumpstarter pack with you on longer tips. Much safer.

mandm said:
ended at 13.4 Volts upon landing
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That's definitely too low. Should be closer to 14V.

The people teaching handproping at OSH told me the angle on a nose gear puts the prop in a non-ideal position. But I saw our aiport manager do it on a Warrior with a stuck Bendix drive. Maybe I should have him give me a few lessons.
 
AV8R_87 said:
With a 12V system, carry a lithium jumpstarter pack with you on longer tips. Much safer.


That's definitely too low. Should be closer to 14V.

The people teaching handproping at OSH told me the angle on a nose gear puts the prop in a non-ideal position. But I saw our aiport manager do it on a Warrior with a stuck Bendix drive. Maybe I should have him give me a few lessons.
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I do have a battery charger that I hook up to the airplane when in the hangar. I checked the data for various flights, and the initial data for flights in March shows an initial voltage as 13.2 prior to engaging the starter. In April and May there are some flights that show 11.1 volts and the airplane still started (including when I flew to Vero Beach for the Piper factory tour, which the airplane was outside and not charging and started with 11.1 volts). A few days later when going to leave, the voltage was at 12.2 volts and when I attempted to start the airplane it started fine, a few stops later, after a quick break, I went to start the airplane as a hot start and the data shows the voltage dropping after attempting to start the airplane unsuccessfully for 7 seconds. The voltage then dropped below 10 volts and even lower on the subsequent attempts to start the airplane. Then it seemed like everything "died", with the G3X powering off and the starter just stopped and did nothing.

I am wondering if the battery is finished (I need to check the date on the battery but it is from the previous owner so it is several years old), and another thing I am wondering is that the G3X is on the battery master (the rest of the avionics is on its own master) and if the G3X should have its own master switch from the starter? Because on the second and third attempt to start the airplane, when attempting to start the aircraft, everything powered off including the G3X, it kind of felt like everything just "died", but it was just for a second and the G3X rebooted immediately by itself.

Looking at all data, post flight data is showing the battery voltage between 13.1-13.4 volts, even after the most recent flight. Is there a charging setting from the alternator? The alternator and starter are both brand new.
 
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mandm said:
Is there a charging setting from the alternator? The alternator and starter are both brand new.
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No, there is no separate setting.

Rate of charge is regulated by the difference in voltage between the battery and the alternator voltages. This makes the voltage regulator the only control you have over charging current.

-Skip
 
The Cessna Alternator Charging Service Manual gives the specs for charging voltage. Note that it changes a bit depending on ambient temperatures, and the settings for the semi-solid-state regulator are slightly different from the earlier electromechanical regulator.

1746674709601.png

The ambient temperature is what the regulator, not the pilot or mechanic, is experiencing.
 
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There's a few basics to check. If you're getting a big voltage drop engaging the starter, could be battery is past its prime. Other possibilities, poor connection between battery and starter, poor ground, starter solenoid etc.
Has the Bogert battery box/cable modification been done?
You say you keep it on a charger in the hangar, which one? Is it an aviation battery minder or an automotive one?
On the master/G3X wiring, that's exactly the way it's supposed to be. It's a primary instrument and should be wired the way it currently is. The reason it's cutting out is the voltage is dropping below a threshold level. That's as designed. The G3X takes minimal power compared to the starter.

A easy first step would be a capacity check on the battery. Most AP's should have a charger/tester that can do this. Also you should have the age of the battery in your log books.

Lastly, I'm going to be a bit blunt. Flying to Iceland, when something this basic mechanically is a mystery, seems a bit of a stretch.
 
Though I’d guess most pilots have succeeded in jump starting or hand propping a plane with a dead battery and letting it charge in flight to no ill effect, I think most manufacturers frown on the idea. Similarly, most frown on charging a dead battery while installed in the plane. The “Most Conservative Action” is to remove the battery from the plane, test it, and then charge it on a bench if it seems capable of it. Or replacing it if in doubt.
 
FastEddieB said:
“Most Conservative Action”
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Careful, Eddie; language like that can get you banned. ;)


FastEddieB said:
Though I’d guess most pilots have succeeded in jump starting or hand propping a plane with a dead battery and letting it charge in flight to no ill effect, I think most manufacturers frown on the idea.
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I think my concern would be based on whether I knew what caused the dead battery. If I found I left the master switch and landing light on, then a dead battery wouldn't be unexpected. But to fly without knowing what ran down the battery? I don't think I'd like to fly with some unknown electrical issue lurking in the plane.
 
I once had another pilot offer to hand prop my 182. While he was successful, I was uncomfortable with the idea considering the angle of the prop on a nose wheeled aircraft is not conducive to a proper follow through.

I've since upgraded to an MT prop with larger high-compression cylinders, so I think hand propping is a "non-starter". I bought one of these off Amazon for the plane; I've used them to jump start cars and they work amazingly well. It can also inflate tires:

https://www.amazon.com/dp/B0BQWG6NQZ?ref=ppx_pop_mob_ap_share
 
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I've hand propped the old 6cyl continental on a 172. I didn't find the angle bad. Maybe it's my height and 6'-7" wingspan that makes it a non issue for me. I'm hesitant to try and hand prop a bigger engine, or anything with a 3 blade though. Less leverage and more compression, nah.

I have jump started off my truck before. On a check ride no less. Renter previous had turned the beacon off, but left the master on. My beacon never shuts off.
 
Brad Z said:
While he was successful, I was uncomfortable with the idea considering the angle of the prop on a nose wheeled aircraft is not conducive to a proper follow through.
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Hand propping a nose wheel plane is known as the "Hemingway technique:" A Farewell To Arms.
 
I hand propped my Warrior a couple of times. Also a few tailwheel airplanes. The angle of the pull on a tailwheel airplane is far better as you momentum carries you away from the propeller. On the nosewheel airplane, since the plane of the propeller is mostly vertical and you are leaning into it, your momentum carries you more into the propeller, which is a bad thing. So it's definitely possible, but be careful. Also, I found the angle of the pull on the nosewheel, combined with the propeller being overall lower, to make it harder to get a good swing.
 
Capt. Geoffrey Thorpe said:
No.
While it's not likely that a glove (or ring) would get caught on the prop, why take the chance?
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I only tried it one time without success, the propeller was too sharp for my hands.
I did hand prop my cox .049 nitro engine on my PT 109 trainer when I was a kid. I remember getting my fingers caught in there a few times and it hurt.
 
Gary Ward said:
I only tried it one time without success, the propeller was too sharp for my hands.
I did hand prop my cox .049 nitro engine on my PT 109 trainer when I was a kid. I remember getting my fingers caught in there a few times and it hurt.
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They need one of those RC motor starters that go on the spinner, but only for Continentals and Lycomings. (F the Rotax guys and their weed whip engines. :P)
 
Hang 4 said:
There's a few basics to check. If you're getting a big voltage drop engaging the starter, could be battery is past its prime. Other possibilities, poor connection between battery and starter, poor ground, starter solenoid etc.
Has the Bogert battery box/cable modification been done?
You say you keep it on a charger in the hangar, which one? Is it an aviation battery minder or an automotive one?
On the master/G3X wiring, that's exactly the way it's supposed to be. It's a primary instrument and should be wired the way it currently is. The reason it's cutting out is the voltage is dropping below a threshold level. That's as designed. The G3X takes minimal power compared to the starter.

A easy first step would be a capacity check on the battery. Most AP's should have a charger/tester that can do this. Also you should have the age of the battery in your log books.

Lastly, I'm going to be a bit blunt. Flying to Iceland, when something this basic mechanically is a mystery, seems a bit of a stretch.
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I am not too familiar with the battery, the battery box, or working in the fuselage space.

I do not have the bogart battery box to my knowledge, my mechanic said it’s expensive to do and wires everywhere. So is that upgrade really worth it if it’s going to cost well over $1000 for parts and labor?

As for the battery charger, I have an aviation batteryminder for Concorde battery.

Good to know about the G3X / master switch.

I could have my A&P test the old battery or I could just buy a new one, at the end of the day, I know the battery is several years old since I have never changed it since owning this airplane, I have the date in my logbooks but those are not with me right now. With the planned trip to Iceland, I don’t want any issues with the battery so I’ll just get a new one. I’m only asking these questions to learn more and answer questions that I have.

If I have my mechanic do testing of the battery, that’s going to cost additional labor, isn’t it just better to replace it with something new?

I’m also traveling soon (by land), so I just want to come back to a working airplane and not have down time trying to fix stuff either.
 
Half Fast said:
Careful, Eddie; language like that can get you banned. ;)




I think my concern would be based on whether I knew what caused the dead battery. If I found I left the master switch and landing light on, then a dead battery wouldn't be unexpected. But to fly without knowing what ran down the battery? I don't think I'd like to fly with some unknown electrical issue lurking in the plane.
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I remember that I left the fuel pump on during a short flight and I left my lights on when I turned the master off, but this was on prior flights.

But looking at the battery voltage, the history is still showing 13.4 volts post flight. If it’s supposed to be at 13.8 volts then it is too low.

I have a Concorde battery and my mechanic is recommending that I buy the Concorde RG-35AXC battery.
 
Gary Ward said:
Do you guys wear gloves when hand propping?
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I didn’t, I thought it was pretty easy and quick to do (few minutes - maybe 10 pulls, although andm says it took me 20 tries), but I could feel the compression building up and I was staying out of the way so I was just placing my fingertips on the leading edge of the prop. I didn’t notice the angle being weird other than trying to use my fingertips to pull.
 
1960's, my instructor trained me on hand propping a Cessna.

Inertia control is essential, you swing your right leg toward the plane with your hands on the prop.

Swing that leg rapidly back as you pull down, releasing the prop and falling to your rear as you let go.

The inertia of that swinging leg is your safety factor.

You do not actually fall to the ground, but catch your motion going back with a few steps away from the plane.

I have hand propped a 215 HP Franklin with high compression, many cold days, without difficulty. Eventually, we had a larger battery installed behind the luggage area for more CCA's.

Paper work for the mod took a long time......

I do recommend gloves, and do not put the end joint of your fingers over the blade, just the tips, in case of kick back, which is common and sharp.
 
geezer said:
1960's, my instructor trained me on hand propping a Cessna.

Inertia control is essential, you swing your right leg toward the plane with your hands on the prop.

Swing that leg rapidly back as you pull down, releasing the prop and falling to your rear as you let go.

The inertia of that swinging leg is your safety factor.

You do not actually fall to the ground, but catch your motion going back with a few steps away from the plane.

I have hand propped a 215 HP Franklin with high compression, many cold days, without difficulty. Eventually, we had a larger battery installed behind the luggage area for more CCA's.

Paper work for the mod took a long time......

I do recommend gloves, and do not put the end joint of your fingers over the blade, just the tips, in case of kick back, which is common and sharp.
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Oh does it kick back? Didn’t know that. Basically I would say I pulled the prop halfway thru a turn and there is a slight delay before it would fire and start, so I’m moving out of the way basically half way through a pull if that makes sense.
 
Kick back is maybe 1 of 10, but can remove finger joints. You are pulling the sharp edge of the prop.

Stationary foot is at least a foot outside the arc of the prop.

I should add that there should be a pilot in the left seat, or tied down plus chocked, and parking brake set. You do not want any chance the plane moves.

If it moves, go to the side, do not run away to the front.
 
Hang 4 said:
On the master/G3X wiring, that's exactly the way it's supposed to be. It's a primary instrument and should be wired the way it currently is. The reason it's cutting out is the voltage is dropping below a threshold level. That's as designed. The G3X takes minimal power compared to the starter.
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That tells me that either the battery is shot, or the master contactor is shot. Some proper troubleshooting is in order here, or else a lot of time and money will be spent throwing expensive parts at the problem. Now to find a mechanic that knows how to do voltage drop tests across the components in the system.....
Hang 4 said:
Lastly, I'm going to be a bit blunt. Flying to Iceland, when something this basic mechanically is a mystery, seems a bit of a stretch.
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More than a bit. It's asking to die.
 
geezer said:
Kick back is maybe 1 of 10, but can remove finger joints. You are pulling the sharp edge of the prop.
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The ignition switch is wired (usually, if it's done right) to ground the non-impulse mag when the switch is moved to the the Start position. This is to prevent kickback. Now, when hand-propping, that mag is not grounded because the switch isn't in the Start position, and kickback is quite possible. One should set the switch to run the impulse mag only, L or R as applicable to that engine, and kickback doesn't happen so easily then. The impulse retards the spark to top dead center or close to it. Don't forget to move the switch to Both after start.
 
Never done it. Did have a couple of guys hand prop a C210 on my field. Got away from them and eat up a C337 across from them.
 
I've hand propped a cub many dozens of times, both wooden and metal props. Never used gloves and I've done it in freezing weather. It think it's most dangerous if you've never had someone demonstrate how to do it in person so you don't know, or if you've done it enough that you get complacent. I wouldn't hand prop an airplane with a starter unless I was escaping from zombies. It's just not worth the extra risk to me, but I will admit I'm a bit of a baby. I don't think someone is necessarily nuts for doing it.

One thing maybe worth mentioning, as I understand it and could be wrong, typically the mags are a bit different on a plane without a starter, so they fire off better at the slower hand prop speeds. Which is awesome, but it also means that there is no speed slow enough to be safe from the perspective of a chance that the engine will fire.
 
Dan Thomas said:
The ignition switch is wired (usually, if it's done right) to ground the non-impulse mag when the switch is moved to the the Start position. This is to prevent kickback. Now, when hand-propping, that mag is not grounded because the switch isn't in the Start position, and kickback is quite possible. One should set the switch to run the impulse mag only, L or R as applicable to that engine, and kickback doesn't happen so easily then. The impulse retards the spark to top dead center or close to it. Don't forget to move the switch to Both after start.
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Oh I haven’t heard about this and when I did it, the mags were on both. I think when someone helped me hand prop it before it was also on both. How can I find out which mag is the impulse mag?
 
Dan Thomas said:
That tells me that either the battery is shot, or the master contactor is shot. Some proper troubleshooting is in order here, or else a lot of time and money will be spent throwing expensive parts at the problem. Now to find a mechanic that knows how to do voltage drop tests across the components in the system.....

More than a bit. It's asking to die.
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My mechanic just went to my hangar and he said the battery is old and looks to be an older model so it’s time to replace it. Plus, it’s the standard model, we are going with the XC model which will be better.

And yes that’s why I’m addressing this issue now before doing flights over large bodies of water. Battery is ordered and will be installed next week.
 
Albany Tom said:
I've hand propped a cub many dozens of times, both wooden and metal props. Never used gloves and I've done it in freezing weather. It think it's most dangerous if you've never had someone demonstrate how to do it in person so you don't know, or if you've done it enough that you get complacent. I wouldn't hand prop an airplane with a starter unless I was escaping from zombies. It's just not worth the extra risk to me, but I will admit I'm a bit of a baby. I don't think someone is necessarily nuts for doing it.

One thing maybe worth mentioning, as I understand it and could be wrong, typically the mags are a bit different on a plane without a starter, so they fire off better at the slower hand prop speeds. Which is awesome, but it also means that there is no speed slow enough to be safe from the perspective of a chance that the engine will fire.
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You guys are instilling a lot of fear in this world, I need to check that all of my fingers are still here ;)
 
I've taught a lot of people how to hand-prop an airplane. First thing you do is look at the plane... is there a nosewheel?... STOP Not worth it. 3-bladed prop?....STOP Not worth it.

Even with many years of hand-propping, hundreds and hundreds of times, I made a horrible mistake once and it could have hurt someone and/or destroyed my plane. I really needed an after-work flight, but my Cessna 140 had a dead battery. I put big, heavy chocks (the kind they use on 18-wheelers) under both tires. I cracked the throttle, turned on the mags, and proceeded to spin the prop. Nothing. I tried and tried and tired until I flooded it. I was exhausted and about to give up at this point. I should have.

Most old tailwheel guys know when you flood it, you turn off the mags, push the throttle full forward, turn the prop backwards a few times and then start the process over. I did this, then turned the mags back on and got out to start propping again. What I didn't do was pull the throttle back out... the engine came to life immediately and several levels of luck saved me. Luckily, I realized immediately what I'd done. Luckily my passenger door wasn't locked. Luckily the monster chocks held and I made it to the throttle before anything bad happened.

Even after all of that work, I shut it down and put it back in the hangar. I was done.
 
mandm said:
You guys are instilling a lot of fear in this world, I need to check that all of my fingers are still here ;)
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:) I am VERY happy that you are OK, and I don't mind admitting, as above, that I am a bit of a baby about these things.
 
Lowflynjack said:
I've taught a lot of people how to hand-prop an airplane. First thing you do is look at the plane... is there a nosewheel?... STOP Not worth it. 3-bladed prop?....STOP Not worth it.

Even with many years of hand-propping, hundreds and hundreds of times, I made a horrible mistake once and it could have hurt someone and/or destroyed my plane. I really needed an after-work flight, but my Cessna 140 had a dead battery. I put big, heavy chocks (the kind they use on 18-wheelers) under both tires. I cracked the throttle, turned on the mags, and proceeded to spin the prop. Nothing. I tried and tried and tired until I flooded it. I was exhausted and about to give up at this point. I should have.

Most old tailwheel guys know when you flood it, you turn off the mags, push the throttle full forward, turn the prop backwards a few times and then start the process over. I did this, then turned the mags back on and got out to start propping again. What I didn't do was pull the throttle back out... the engine came to life immediately and several levels of luck saved me. Luckily, I realized immediately what I'd done. Luckily my passenger door wasn't locked. Luckily the monster chocks held and I made it to the throttle before anything bad happened.

Even after all of that work, I shut it down and put it back in the hangar. I was done.
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Oh yikes, I mean I guess I only did it because I have a hand brake that acts like a parking brake in a car. If I didn’t have this, not sure that I would have done it. I might have been in the cockpit and sent “andm” to do it after some trial lessons. We both attended the hand prop class at Oshkosh as well.
 
mandm said:
Oh yikes, I mean I guess I only did it because I have a hand brake that acts like a parking brake in a car. If I didn’t have this, not sure that I would have done it. I might have been in the cockpit and sent “andm” to do it after some trial lessons. We both attended the hand prop class at Oshkosh as well.
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It's always best to have someone at the controls who knows what they're doing, but even then the first thing I teach is pull on the strut to make sure they're holding the brakes hard enough. You'd be surprised how many times the plane has moved. Second best is to tie the tail. Third best would be to chock the plane. I never trust a parking brake!

You did fine and survived, with all of your fingers, but I don't recommend doing it again on a tricycle plane! Remember the hand prop class is taught on an Aeronca Chief!
 
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