Starting round engines

I've been traveling for a few days so haven't been following this.

As for deferring the primers, primers do not appear in 91.205 as required equipment for daytime VFR (nor IFR, nor night). There is not a MEL for the aircraft that I can find. I honestly don't remember whether the primers were placarded. So as far as I can see primers are not required. (I no longer have the POH available to me so if someone has it please educate me.)

Priming the engines with the throttles as noted above, is not in accordance with the POH. Pumping the throttles without the mags on and the engine turning would clearly violate the POH note. But we never did that. It was always after the engine was turning over and with mags on. At what point does it become manipulating the throttles to start the engine as opposed to priming the engine? And what is the risk of fire pumping the throttle while cranking with ignition on? Apparently low enough for the people who own the airplane and have operated it for hundreds if not thousands of hours. Are they wrong? Given that I had 0 hours of radial time, I accepted that they knew the plane. Is that foolish? Perhaps, but I really don't think so. Have I had experiences while training that I looked back on after getting more experience and thought "I wouldn't do that again." A few. If I have a question, I ask it. This did not occur to me to question.

I'll also note that I've rarely seen (I'd like to say never, but in 20+ years I might miss something) a POH that has instructions for "properly starting the engine" that say much specific about primers or throttles other than some variation of "as required" or "idle/cutoff"

I'd have been very content if someone had come along and said "Hey, here is the sequence they should have followed." rather than belittling my knowledge and my desire for learning. If I didn't have a desire to improve, I wouldn't have bothered to post in the first place.

I now have a whopping 6 hours of time behind radial engines. I'm am quite sure I have a heck of a lot to learn.

John
 
It's been a long time, but I think the primer is in the carb.

2351a52890d83db58e6c2400af9a38e4.png

From a wasp jr manual. Circa 1962.

So depending on model of carburetor, the primers may have been disabled.
 
Tools said:
Dear heavens! No wonder jets have taken over…

To wit, A-4 Skyhawk:

Hold up 1 finger
Hold up 2 fingers
Push throttle from off to idle
Hold up 3 fingers
Hold up 4 fingers
Click to expand...

What were the individual fingers signifying? For us, it is the "a ok" thumb to index finger with the other 3 up, to signal APU start. Then shake 2 fingers to crank the right, followed by one finger to crank the left. Interesting
 
35 AoA said:
What were the individual fingers signifying? For us, it is the "a ok" thumb to index finger with the other 3 up, to signal APU start. Then shake 2 fingers to crank the right, followed by one finger to crank the left. Interesting
Click to expand...
No APU/GTS on A-4's, used a start cart ("huffer") to spin up the engine.

IIRC, and with none of the cues:
1 - huffer on/connected
2 - air on
3 - air off
4 - disconnect


Nauga,
and his yellow gear
 
Nauga nailed it…

1. Electricity on, this was necessary for the igniters.
2. Air on.
At 12-15 percent n1, goto idle. This activates igniters and introduces fuel.
3. At 45 percent, air off.
4. When your gyro quits tumbling, disconnect power. Generator comes on automatically.

On the ground they were as busy as a one legged man in a arse kicking contest.

And then it gets REALLY hectic.

Turn on radio.
Turn on transponder.
Turn on TACAN.
Set 4 deg nose up trim (no matter the load).
Set 1/2 flaps.

Remember to rotate at 150 kts.
Land at 15 units AOA.

Now y’all are checked out in a A4!
 
The T-38 also used a huffer.

The ground crew fired it up while you were strapping in. Aircraft controlled the air.

Push start button (fires ignitors and turns on air)
At some RPM (maybe 15%) you put the throttle in idle.

Once you start both engines, the ground crew automatically disconnects the huffer.
 
Salty said:
So hand propping a plane with a dead battery is flying a non airworthy aircraft now. Sorry, but if you are concerned that people are flying planes even though the primer isn’t working you need a life.
Click to expand...
You really should stop posting on things you know nothing about.

The practice the OP is talking about is asking for a fire and why most of the round engine airplanes I fly have notes in the manuals to specifically NOT pump the throttle.
 
jsstevens said:
For the record, the primers were enroute but had not arrived. They fully intend to fix them. But it’s not a grounding issue.

And that misses the whole point of my question: what tells you the engine is ready to start?
Click to expand...
You really need to be asking them.

It is clearly an abnormal procedure that they have developed and sounds like it works, but not something I would attempt without consulting someone with more Beech 18 time than I and I have almost 600 hours in mine.
 
DavidWhite said:
Thats significantly different than my start in the beaver. 10 (IIRC) pumps of the primer and a couple pumps of the throttle. Always started on the second or third blade. I did the same thing for the 1340 in the Norseman and it seemed to like that too.
Click to expand...
Why did you need to pump the throttle at all?

Granted, start procedures can vary between airframes based on differences in installation, but my T6 manual (R-1340) under engine start has it highlighted in bold: Do Not Pump the Throttle
 
jsstevens said:
I've been traveling for a few days so haven't been following this.

As for deferring the primers, primers do not appear in 91.205 as required equipment for daytime VFR (nor IFR, nor night). There is not a MEL for the aircraft that I can find. I honestly don't remember whether the primers were placarded. So as far as I can see primers are not required. (I no longer have the POH available to me so if someone has it please educate me.)

Priming the engines with the throttles as noted above, is not in accordance with the POH. Pumping the throttles without the mags on and the engine turning would clearly violate the POH note. But we never did that. It was always after the engine was turning over and with mags on. At what point does it become manipulating the throttles to start the engine as opposed to priming the engine? And what is the risk of fire pumping the throttle while cranking with ignition on? Apparently low enough for the people who own the airplane and have operated it for hundreds if not thousands of hours. Are they wrong? Given that I had 0 hours of radial time, I accepted that they knew the plane. Is that foolish? Perhaps, but I really don't think so. Have I had experiences while training that I looked back on after getting more experience and thought "I wouldn't do that again." A few. If I have a question, I ask it. This did not occur to me to question.

I'll also note that I've rarely seen (I'd like to say never, but in 20+ years I might miss something) a POH that has instructions for "properly starting the engine" that say much specific about primers or throttles other than some variation of "as required" or "idle/cutoff"

I'd have been very content if someone had come along and said "Hey, here is the sequence they should have followed." rather than belittling my knowledge and my desire for learning. If I didn't have a desire to improve, I wouldn't have bothered to post in the first place.

I now have a whopping 6 hours of time behind radial engines. I'm am quite sure I have a heck of a lot to learn.

John
Click to expand...
Maybe I missed it, but I'm not seeing anyone really belittling you. I think several of us are just surprised that an outfit operating the aircraft for flight training would be doing that.
 
Fearless Tower said:
Why did you need to pump the throttle at all?

Granted, start procedures can vary between airframes based on differences in installation, but my T6 manual (R-1340) under engine start has it highlighted in bold: Do Not Pump the Throttle
Click to expand...

Was told to pump the throttle. Lol
 
Depends on the carb installed on the 1340, 985. The later models had the accelerator pump set up to prime the engine. If what the service manual said is correct. On 1830's I do remember using primers every time. And the r 2000's.
 
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