Air Start

[helipan]

Hi Just wondering if anyone has done an air start, I would imagine you would be busy in an auto and do you need your knees to hold the cylic, Both the r44 and the B206 manuals talk about but is it as easy as that,

[Flying Pencil]

Have only had to do it in a Hughes 269. Had a student on board which should of made it easier but you have to talk them through it really cos its hard to reach the starter from the co-pilots seat. Makes for an interesting post flight discussion over a cup of tea!!(Or a large gin)

[havoc]

number one question pops to mind....why did the engine fail that you have to restart?

Teaching UH-1s at Rucker I tried to let the students do this in the Sim, started at 10000 feet, 2 students and always let them table talk what they where going to do before hand. Not many got it done, and also tried with 2 IPs.

Good coodination drill, it also generated alot of discussion about thinking thru EPs, back to question 1.

[ramen noodles]

Airstarts have many bad possibilities, mostly involving the diversion from the job of maintaining a good autorotation. Crowding an airstart into an off-site emergency landing is liable to produce a case where neither is done well, and a fatality is the cost.

Best method, memorize the steps so that you can say them in the shower automatically, run your hands thru them while sitting in the cockpit (and perhaps holding the cyclic in your knees!) and then enter auto while in typical cruise, and practice running your hands thru the mock re-start while maintaining an auto glide to a prospective landing spot. This practice is golden, and should tell you if you have the ability to attempt a real one.

If the engine conks out, for real, don't dare try a restart unless:

The above practice has been impeccable
The situation is not pressed (enough altitude, an easy landing spot, an easy glide to it)
The engine failure cause is reasonably known ("Ouch, I forgot to switch tanks!", or "Gosh, I twisted the throttle closed too fast!")
You are feeling lucky.

[flyer43]

I couldn't agree more with both Ramen Noodles and Havoc. Have lost the engine in a Bell 47 below 500 feet once, so no time to even think about restarting but if the same had occurred at several thousand feet, I would have concentrated first on ensuring I could make it into a safe landing area before even looking at trying to restart.
I would only attempt a restart if I was aware of the reason it had failed - as RH & H have mentioned already. If you don't know what caused the problem and succeed in restarting the engine, you may be lulled into a false sense of security and continue the flight in the belief that all is OK now, only to place yourself in a worse position when the engine fails for the second time..... or catches fire etc........

Have had to restart an engine in a twin, but that is no real sweat unless you haven't assessed your performance correctly and can't maintain altitude on the remaining one!!

[Lama Bear]

Two. Both in Bell 206's. It's not that big a deal once you have your airspeed, RPM and crash point established. Helps to have altitude but one was done almost as an auto relight.

[Shawn Coyle]

If you read the Rolls-Royce manual on the 250-C20 series engines, I believe there is a relight procedure that states something to the effect of 'within the 1st 10 seconds, just hit the starter button' with the throttle still full open. It's what the autorelight does...
But it's not in the Bell manual for reasons that have always escaped me. It was in the OH-58A manual if my rapidly failing memory hasn't let me down again.

[skadi]

As far as I remember from my former BO 105 checkrides, where we sometimes practised air restarts, these 10 sec ( or was it 1 min? ) with the 250-C20 series engines relighting procedure have something to do with the rapid cooling of the compressor due to the airspeed in flight , so theres some danger, that the compressersection get stuck and a proper engine starting wouldnt be possible.

skadi

[helipan]

In a R44 Astro the starter does not allow you to start again until the clutch has disengaged/stopped e.g when on the ground and after you have just started the engine and stalled on a cold morning 0 degrees, so how will it restart in the air.
It must be possible because the R44 manual talks about it!

[MrEdd]

In the Schweizer 300 the air starter "activates" when the M/R gearbox reaches 2 1/2 PSI, could that be about the same function for the 44?

[FH1100 Pilot]

In a helicopter (especially a single-engine), the procedure for an air start is largely theoretical.

[Shawn Coyle]

I watched an airstart in a Bell 407 during my days at Transport Canada - it will restart below 10,000 feet. Didn't seem too different than the normal ground start.
Having started at nearly 20,000' and tried twice with no start at high altitude will give you an idea of some of the issues.
That's why auto-relight should be standard for turbines.
Should be armed automatically anytime there is pressure in the transmission and the throttle is open.
Not sure what I'd do for a piston engine machine - the main problem is that unlike a FW airplane, there is no propeller to keep the engine turning over.

[the beater]

helipan...

NONSENSE!!!
It is perfectly possible to start an R44 with the clutch engaged.
The reason you can't start after stalling is that the clutch motor is still travelling. Once the clutch travel light extinguishes you can use the starter motor with the clutch engaged or disengaged.

I seriously hope that you are not qualified to fly the Robinson R44 (or 22) as this is covered in basic training.
If you are, then you'd better have a word with your instructor.:mad:

[helipan]

Thanks "t beater" for that info but where can I read it myself,
Not all of us have received the best training! buts thats why we get on this site and try to find out what happens and why? We also find out how things work...and to learn more about the aircraft.

Thanks for all the comments

[Windy Pants]

...make sure that you have sufficent RRPM (assuming you're still on the ground) as if the clutch is engaged and belts have fully tensioned, with insufficient RRPM might lead you to break something when you try the restart. It's just like starting a car when it's been left in gear.

[the beater]

Helipan;
I apologise if what I posted seemed a little abrupt. It wasn't meant to be.
The fact is that all the emergency procedures in the POH should have been gone through during your training. Part of the training that I teach for forced landings always covers the possibility of a re-start (assuming that you don't jeopordise carrying out what is likely to be an EOL). An engine can stop for a number of reasons that aren't necessarily engine failure, such as carb icing, inadvertent application of the mixture control or even a 'lean cut'. I just don't understand why this procedure wasn't covered; it's one of the questions that I often ask during my work as an examiner (and don't worry, you're not in the minority in not knowing the answer, another popular one of mine is asking the candidate to show me how to check the landing lights (I'll give you a clue, it also involves the clutch)).
In fact, I struggle sometimes to find enough malfunctions to cover in the Robinsons.
But trust me; time spent on covering all aspects of the emergencies and malfunctions is never time wasted.
You ask where you can read it.

You just have!!;)

[verticalhold]

One thing to watch in a turbine is the mass airflow. The re-start needs careful monitoring because the forward speed is stuffing a lot more air in than a static start on the ground. Get a bit carried away and you can get a BIG overtemp.

Did it once in an S61 which tried to overtemp and once in a 332 which was warm, but within limits. Seen it in a 355 and it was a non-event. On the S61 we gave up and continued on one, the 332 was following a precautionary shut down when base engineering advised (as did the book) having the engine going for the arrival. Always wondered that bit as the 332 was always so powerful.

VH

[sneetch]

I trained in a R22 and now have a couple of hundred hours. Everything I know about air restart procedures, I learned from the POH. It was not once mentioned by my instructors (both very experienced pilots). Ofcourse, I should have asked! I suppose that I assumed I lacked the skill required to perform an auto and attempt a restart at the same time.

Cheers