Airbus, A350, APU start close up.

[@dipling.pitzler7650]

Amazing that the video even catches the clicking of the igniter !

[@dennisvijverbergbrakesrele6098]

Yes it is

[@victorgc_]

Well, you'll realize that those are noisier than you might think so. On some turbine aircraft you can even hear them a dozen or so feets away during start-up (even APu's)!

[@davecrupel2817]

Oh those puppies are loud. It isnt that difficult to hear them.

[@Katchi_]

If you can't hear them you are deaf. Not talking some small gap spark plug.

[@Rasscasse]

I’ve never watched anything like this before, thank you for posting Dennis. It’s educational and interesting.

[@dennisvijverbergbrakesrele6098]

Glad you enjoyed it

[@bekkerthesokuangeldragon68]

Man i love that sound of jet engines and APU's starting up and shutting down and the idle sounds and the fluctuating turbine sounds. Just sounds so awesome and sick! i'm also a private pilot too that flies private planes. i also like the piston engine sounds ones too

[@timothyharrison8953]

When I was in the Air Force and a Dedicated Crew Chief on the KC-10s, the airplane I crewed had an issue with the APU on startup. It would shoot a nice long fireball for a few seconds, but it was never out of starting EGT limits, and always extinguished. Now, we new it was a problem and all LRUs and troubleshooting knowledge was attempted, but nothing fixed it. Replacement was the only solution, but none were available at the time. Problem was when we'd go to other bases, someone would see the flames, panic and call the fire department. It was replaced eventually. So, since retirement and entering civilian life working for an aircraft production company, starting newly installed APUs and engines that are preserved, is always fun. I've seen some pretty good flames from both and it never really scares me.

[@dennisvijverbergbrakesrele6098]

It normally should not do it, but I have a seen it a couple of times more. And most of the times as long it doesn’t exceed any parameters or have to many auto shut downs the APU will remain on the aircraft.

[@robertbemis]

141's we're hella scary to start too.

[@allen480]

@@robertbemis I miss the C-141B

[@MandoMonge]

I’ve operated on that aircraft 3 times. Funnily enough, it also suffered a FWD cargo fire once and had to do an emergency diversion. Great video

[@alphaforest]

Inibuilds modeled even the APU perfectly

[@EasyTiger654]

Amazing to think this is the Honeywell-331 which actually is a full size turbine engine on the Cessna Commander and Mistusbishi Solitaire, an awesome engine in its own right.

[@Spinex0196]

your telling me that this shi has afterburner?

[@tmothymccutcheon7432]

That's a marshmallow roaster 😂😂😂😂

[@Spinex0196]

@@tmothymccutcheon7432 I might be late but those emojis cringe af

[@Gale24]

@@Spinex0196 💀💀

[@cellpat7392]

I work at an airport and I've seen this happen a few times. it is interesting as you catch it only by chance. Only one day one of their smaller jets APU had a hiccup and let out a tongue of fire. they had to put it out of service to repair it, an MX man told me.

[@tomstravels520]

Do you ever do software updates for these aircraft or does someone else do those. Would love to see how computers like the PRIM's are updated. There was a recent one that then needed a patch as it could cause a problem on the A350

[@dennisvijverbergbrakesrele6098]

As we are a line station we do software uploads when a change of a Line Replaceable Unit is required and that one needs particular software part number to run. Could make a video of that if ever it passes by.

[@rexfordluke1480]

@@dennisvijverbergbrakesrele6098 am eagerly waiting for that vid, sir. Thank you in advance ☺💯

[@MrEeeaddict]

@@dennisvijverbergbrakesrele6098 it's updated off the plane?

[@DanSlotea]

Still using 3" FDD s for updates?

[@ONBOARDKLM]

Imagine this during a flight: update ready to be installed, must restart the device... 🎉

[@luchiyasafarova2769]

Это вспомогательное пусковое устройство для вырабатывания электроэнергии для запуска основных двигательных установок?

[@dennisvijverbergbrakesrele6098]

It’s indeed an Auxiliary Power Unit, with the A350 it provides electricity on the ground and bleed air for airconditioning and engine start.

[@NeoRipshaft]

Awesome, and an accompanying video answered my question on if it was getting any ground assistance or able to independently start on the ground using an electric starter - and turns out it's the latter, it's able to start independently using an electric starter.

[@dennisvijverbergbrakesrele6098]

Glad it helped!

[@MarkoVukovic0]

Very interesting, thank you for sharing! I read that these units produce about 200shp, amazing!

[@blazept567]

wow! afterburner 😁💥

[@ImperrfectStranger]

That's the first time I've seen flames coming out of an APU (that wasn't on fire). Did that coincide with the EGTs rising from 620 to 680? 3:37 Is it normal for the igniters to fire before the door is open? Does the door have in inflight mode? Thanks

[@dennisvijverbergbrakesrele6098]

Looks like during start up the APU had a surge ( unstable airflow ) which could explain the rise in EGT. But APU recovered and run normal the rest of the time.

[@Greatdome99]

The APU inlet door has a switch that activates when it opens. That allows the start sequence to begin, not the other way around. All modern APUs are flight capable, but only up to 20,00 for bleed air, 43,000 for electrical.

[@lonistewart3405]

Glory to the APU! 😂

[@allen480]

@@lonistewart3405 I had a APU for lunch yesterday.

[@lonistewart3405]

@@allen480 🤣🤣🤣🤣🤣

[@ekspatriat]

Is an APU for redundancy or is getting power from one or more of the engines a no-no or too complicated?

[@dennisvijverbergbrakesrele6098]

Not a redundancy, more a backup. With jets like B787, A350 and operating APU is not even a requirement for ETOPS flights. But a working one surely makes life easier. For ETOPS beyond 180, and working APU is a requirement.

[@xzreai1802]

Wow amazing video, thank you truly Dennis!

[@jonatanbukit6527]

This is useful,I am a new comer on a350-900/1000 a/p mechanic 👍🏻

[@sw3895]

Excellent

[@radhakrishnansivaramakrish9902]

Should you require to start APU in flight is the air inlet hatch can withstand high winds

[@dennisvijverbergbrakesrele6098]

Yes, it will go to a flight position (less open), all is designed so it can be used during flight.

[@radhakrishnansivaramakrish9902]

@@dennisvijverbergbrakesrele6098 Thank you

[@pilotpawanc]

The correlation between what's happening in the cockpit and outside is what sets thos video apart Kudos!!! However the last few minutes are just repeat; I wonder if i am missing anything.

[@HotelPapa100]

Just an uninterrupted outside sequence.

[@gdessario5014]

Hello from Ontario, Canada Dennis, thanks for posting! That clicking noise, is that the igniters for the combustors in the APU? Thanks!

[@dennisvijverbergbrakesrele6098]

Yes, that noise is from the igniter sparking, it comes on at about 5% N2 and shutdown around 50%, at that point combustion is self sustaining.

[@gdessario5014]

@@dennisvijverbergbrakesrele6098 Ahh, thought so. It was cool seeing the exhaust gas temperature and N value😊. Thanks!

[@rredding]

Now...THAT'S what I call a terrific flight simulator! Well done!

[@davecrupel2817]

Well...if it was a simulator, I'd agree with you.

[@tomiokakanrafire]

Thank you movie! Beautiful sound

[@naturallyherb]

The flame occurs very briefly at 4:29

[@KP-wt8qr]

It's obvious that this is CGI.

[@N9197U]

Its real bro@@KP-wt8qr

[@Matt.Thompson.1976]

Riiiiiight, and the world is flat, and we faked the moon landing!!😂🤣😂🤣@@KP-wt8qr

[@azharhadi7761]

Supra airbus

[@nmarks]

I was an airport one evening waiting to board my fligjht. From the windows I could clearly see about another six or seven aircraft at their respective gates. Suddenly a lick of flame came out of the back of a 737 and I didn't know what it was, so I went over an attendant and (quietly) I told them what I had seen - just in case there was some problem with the plane. She looked like she was about to call security on me! What neither of us knew (she should have known working at an airport) is that the flame was probably the 737's APU starting up, like the one in this video.

[@gaelenski_]

Not really in a flight attendants interest to know things like that. It’s a customer facing role, not an engineers role.

[@richardbriansmith8562]

Awesome Video🙂

[@dennisvijverbergbrakesrele6098]

Thanks 😁

[@tac-cobserver3788]

Awesome 🤙

[@dennisvijverbergbrakesrele6098]

Thanks 🤗

[@krisgreenwood5173]

We called them hot starts. There should have been a corresponding temperature reading on the EGT. But, if it doesn't exceed the parameters, no foul.

[@dennisvijverbergbrakesrele6098]

There was just a small spike on the egt during the event.

[@daveyr5462]

4:29 APU farted 🤣

[@hamentaschen]

As I read this I farted too. Twice!

[@southpark5555]

4:29 nice.

[@DaPlenThing]

I was wondering do spy’s provide any thrust like if you lost your engine thrust would the apu help you get to an airport

[@dennisvijverbergbrakesrele6098]

APU’s only provide a neglectable amount of thrust, it will not help getting you to an airport. It can just provide you with electricity and bleed air.

[@themoonz3928]

Thats One hell of a lighter!

[@kemi242]

What is the clicking sound at 1:20? Sounds like a gas stove igniter.

[@dennisvijverbergbrakesrele6098]

These are the igniters.

[@KenKen-ui4ny]

Your are pretty much hearing the same thing to what you hear happen when you turn on a gas stove, but in big scale.

[@AviationShots._]

Why did the flames come out from the APU exhaust pipe? Is it normal?

[@dennisvijverbergbrakesrele6098]

No not normal, but have seen it before. Looks like APU had a surge ( unstable airflow ) which caused pressures within the APU to change an causing the flame to escape, but APU recovered itself.

[@johanveltheim4331]

A common occurrence in small (or old design) turbines during startup. A turbine engine goes through multiple funny stages during a startup before it runs in a way that can produce power.

[@Greatdome99]

Wet start, not routine, but harmless. Main engines do the same sometime.

[@wallacegrommet3479]

Pilot had to light his cigar

[@Maxumized]

I wonder if the APU pushes the plane forward when running?

[@dennisvijverbergbrakesrele6098]

Nope, brakes on chocks in place, aircraft doesn’t even move when engine are at full power, in that configuration.

[@Maxumized]

@@dennisvijverbergbrakesrele6098 Thanks

[@echohunter4199]

I’d be the guy with a 30 foot long marshmallow toasting stick standing at the back of the APU waiting for the EGT’s to get high enough.

[@brianmckillop5017]

So thats what was at the back of the batmobile

[@Ranjitzu]

I am curious to if this APU can be used in-flight due to how the Flap is constructed on this A380, those I have usually seen have the hatch opening inwards whiles this one opens outwards - can you use this APU while up in the air?

[@dennisvijverbergbrakesrele6098]

APU is designed to be used during flight if needed. Not all APU intakes are the same, some open inwards others open outwards. Normally if used during flight the APU intake flap opens less open than on ground.Almost all APU are designed to be used during flight. But for example an APU of a B747 is inhibited during flight, although if you keep it on during the takeoff you can keep it on until FL250.

[@Ranjitzu]

@@dennisvijverbergbrakesrele6098 Ahh I see, thanks for the explanation - got my question answered, thank you :)

[@Scott_T_]

So the A350 does have an afterburner 😊

[@kenmohler4081]

Only on the APU.

[@MiG82au]

Technically, if the burning fuel you see was injected before the turbine it's not afterburner :p

[@kenmohler4081]

@@MiG82au I think we both knew that. But it was a good spot for a little humor.

[@Olant.]

Amazing Video. Thank's so much!

[@dennisvijverbergbrakesrele6098]

Glad you liked it!

[@Olant.]

I watch it over and over! 😊

[@iGemera]

keep upload more

[@WarbirdPhoenix]

4:29 Alright! We're having bbq on this flight! They fired up the grill!

[@joansmith8215]

Sounds like trying to get my grill lit on my cooker

[@dcdanger6151]

what powers the APU during it's startup if there are no ground services ?

[@yohannessulistyo4025]

Battery

[@dcdanger6151]

@@yohannessulistyo4025 it sounded as if the APU was being charged (spun over) with air pressure. I assume this air is being provided by a battery powered air compressor again my assumption.

[@dennisvijverbergbrakesrele6098]

Battery will provide electricity to the starter/generator of the APU to start it, if no GPU available / connected.

[@Taffeyboy]

How many KW on the generator side?

[@ziauddin7948]

nice A 350 APU start burning flame but does APU needs fuel combustion ?????🇵🇰

[@dennisvijverbergbrakesrele6098]

Yes it needs fuel otherwise it will not work.

[@connorspies]

Is the APU capable of operation while in flight on the A350?

[@dennisvijverbergbrakesrele6098]

Yes, APU can work when in flight.

[@diemc7a1]

@@dennisvijverbergbrakesrele6098Can it provide some thrust?

[@TheFalseShepphard]

​@@diemc7a1 Use your brain and then think about your question

[@vedymin1]

Nope, apu is there only to provide electricity and air under pressure. Any "thrust" would be negligable to a point of not mattering :)

[@Greatdome99]

500 pounds or so. It's a turbine engine, not a jet. Turbines have more turbine sections than jets. @@diemc7a1

[@UQRXD]

Run a city block off that thing?

[@dennisvijverbergbrakesrele6098]

150KVA should be goed for that.

[@mystereit73]

how much power does an APU like this generate...in kw?

[@marinopacentrilli9533]

On the airbus and boeings the apu generator puts out the same power as the individual engine generators meaning any one of the sources can power all the buses. On the narrow bodies it's in the vicinity of 50 kw but I'm guessing a bit I can't recall the exact numbers.

[@mystereit73]

@@marinopacentrilli9533 more than i thought. thank you!

[@dennisvijverbergbrakesrele6098]

APU generator can deliver 150KVA max continuous on the ground.

[@b43xoit]

@@dennisvijverbergbrakesrele6098 How much addt'l power in the bleed air?

[@mingming9604]

It;s a mini turbine jet ;)

[@TankEnMate]

Weird that everything is in metric except for the bleed pressure.

[@waldoinaz]

Amazing. Can’t wait for you to show bread popping out of the toaster. Riveting stuff.

[@TheV4R]

for one second at the thumbnail i thought it was a fighter jet being mistaken for an a350

[@ben_doom1958]

A350 afterburner. Takes pretty long to start...

[@lewistempleman9752]

why does engine start?

[@dennisvijverbergbrakesrele6098]

Needed to supply air to the airconditioning to cooldown the cabin.

[@colinashby3775]

Subscribing. What sort of thrust do these APU's put out?

[@TalasDS]

Basically zero. APUs have no baffle to speed up exhaust air flow, hence little to none thrust is produced. Which is fine, considering their purpose is solely to generate electricity and compressed air.

[@dennisvijverbergbrakesrele6098]

If APU runs during the flight the thrust given in neglected. It’s there to provide electricity or air for the air conditioning system.

[@ChrisCokeRobinson]

0 thrust

[@Heyman1982]

@@dennisvijverbergbrakesrele6098why would the apu run during flight? Don’t the engines provide all the electrical power once running?

[@dennisvijverbergbrakesrele6098]

Normally APU would not be used during flight. It would only be started in the air when procedures ask for it. If for instance one engine is shutdown, dual generator failures, failure with engine bleed air supply. In normal operations APU is only used on the ground, to provide air and electricity, when the engines are shut down

[@陳亭蓁-u7s]

How about shutdown?

[@mofukiicat5431]

I didn't know that flames come out of them

[@dennisvijverbergbrakesrele6098]

It normally doesn’t, but this time it looked like ignition of the fuel was a bit late.

[@PRCOM]

Lot of fuel 75.1 going somewhere nice 😊

[@dennisvijverbergbrakesrele6098]

That's the plan!

[@fastica]

This is basically an airplane farting.

[@TheBestFriendscoltd]

Registration?

[@dennisvijverbergbrakesrele6098]

A7-ALZ

[@TheBestFriendscoltd]

@@dennisvijverbergbrakesrele6098 thanks!😀 It's Qatar Airways right?

[@dennisvijverbergbrakesrele6098]

Yes it’s a Qatar airways aircraft

[@TheBestFriendscoltd]

Painted in OneWorld livery

[@leakd]

GYATT

[@achille8545]

Vidéo parfaite ! 👍

[@CrazyForCooCooPuffs]

idles at 94%?

[@sidnjessswq]

Why all the trouble of a complicated turbine just slap a diesel generator in there great fuel savings aswell

[@lordxandalf]

Redundancy

[@dennisvijverbergbrakesrele6098]

A gasturbine has a better power to weight ratio than a diesel generator. And in aviation everything is about weight. Also the gasturbine is easy to maintain, you only chance oil filters and ignitors on time, no need to change oil, change injectors etc …

[@sidnjessswq]

I dind’t knew that thank you

[@ravindramahuli6213]

What next?

[@คนโง่แก่ๆคนนึง]

Look like hot start

[@dennisvijverbergbrakesrele6098]

Hi there, possible, EGT had a little spike.

[@jankrusat2150]

That APU seems to hve a problem. It should not have flames coming out of the exhaust. it looks like a hot start or excess fuel in the combution chamber.

[@jaystengel7511]

Apu had taco bell earlier

[@Andy-rk9mu]

what if APU fails?

[@marinopacentrilli9533]

The aircraft becomes totally dependant on ground services. Which means they have to leave a engine running till ground power is connected which poses additional risk to ground personel. The apu provides electrical power and pneumatic power for air-conditioning and engine starting. We can dispatch a aircraft with a disabled apu but it makes everybody's life more difficult.

[@Andy-rk9mu]

@@marinopacentrilli9533 thank you. So there is still a main power unit somewhere I assume to provide energy in flight...

[@jopetti]

@@Andy-rk9mu The engines?

[@marinopacentrilli9533]

In flight the engines provide electrical and pneumatic power should you lose both engines and have no apu your down to batteries for the most critical functions and a ram air turbine which deploys if the buses are not powered but your gliding. Manufacturers use the ram air turbine for electrical and hydraulic power.

[@makantahi3731]

slow start

[@dennisvijverbergbrakesrele6098]

Don’t think so, probably the start up fuel was ignited a bit late, and some fuel had go passed the turbine.

[@makantahi3731]

@@dennisvijverbergbrakesrele6098 on an32 apu is spun up with electric motor in 5 seconds and more 3 seconds is needed to enter into idle

[@RBMK_1000]

This is a fart.

[@engchoontan8483]

Intake (of APU) is for drag defeat of top 2 halves of fuselage (before tail-rudder and can protrude due to air drag-defeat suction (when plane is horizon"+10deg" cruise). Cool guard-band is another intake Cool shaped thrust is another intake at exhaust-section Intake funnel vents hinge point should not be at edge and should be parallel-small-rotate then rotate. Air drag auto-mechanical "close" should be negative angle (to air flow) then rotate out. Put together, the front edge is negative angle to air flow, air drag smooth and low torque push out to parallel, then air drag throw open angular-distance(oval rotation) Why turbo-prop parallel shaft for turbo-fan...? Because easier to put arsehole. Thrust vector via intake vent control is not for civilian. BBQ is... no parallel, no aor guard, backpressure from arse no vent

[@engchoontan8483]

Pressure thrust from APU is for main engine efficiency only. Pushing main-engine blades against air(ram-air) for "initiated-established" flow.

[@engchoontan8483]

Exhaust is 2 cones. Thrust is inner cone. Outer cone have vent-vanes angled backwards at sides to drag air in for cooling and prevent backpressure. Charge one tank of pneumatic air, spool APU real slowly and maintain rotation, ignite combustion chamber, flow lubricant, ignite, flow fuel ignite, flow fuel, ignite, flow fuel-air, ignite, check chamber temperature, continue fuel-air flow and ignite, dump tank of air at exhaust for sucker intake. Test with clutched-electrical-power-drill... see how many rotations and how much BBQ effect and play different effects.

[@engchoontan8483]

Oops

[@engchoontan8483]

When bicycle wheel have a dynamo rotated locked to tire... it is difficult to pedal. When APU, smaller engine is providing electrical and 2 main engines are providing thrust (without additional load on 2x big), the 2x spares are balancer to electric-versus-kinetic(rotation)

[@engchoontan8483]

Airbus build pistol arsehole lousy

[@johannesbols57]

APUs do not emit flames, Einstein.

[@dennisvijverbergbrakesrele6098]

This one did, just for a moment.

[@billmalec]

ZzzzZZZzzzzz

[@munkofrolov1963]

4:30 LOL

[@mjlivie]

IF THERE IS ONLY ONE APU WHAT HAPPENS WHEN IT FAILS MID AIR IN FLIGHT OR IS THIS ONLY NEEDED UNTIL MAIN ENGINES TAKE OVER

[@dennisvijverbergbrakesrele6098]

It normally isn’t on during the flight. It’s just a backup, for if they need it, and if it fails then to, I suppose they would try to get to the nearest suitable airport. But the need for an APU to run during the flight is rare on an A350.

[@bigdaddy3662]

Boeing engineers watching: what is this, it's magic from the future