APUs: "Look what they need to mimic a fraction of our power!"

@jameswest8280

18 күн бұрын

It's hard to fathom isn't it? All it takes is a flip of a switch compared to 5 groundcrew, 3 GPUs and a huffer cart.

I saw you lots of times in Qatar and I didn't know you had a KZread channel. Excellent.

@dennisvijverbergbrakesrele6098

8 ай бұрын

Now you know 😉

Hermoso video muchas gracias

A 787 with an INOP APU?!...unheard-of!

@jameswest8280

18 күн бұрын

Yeah, it's not like it happens every day.

Nice 👍

@dennisvijverbergbrakesrele6098

6 ай бұрын

Thank you! Cheers!

APU inop, 1 GPU failed, sounds like a typical workday to me. That Trent sounds awesome.

@dennisvijverbergbrakesrele6098

8 күн бұрын

It does!

Dear Lord, three GPU`s I knew the plastic princess was heavily electric but sheesh, crazy they have all the hookups for three as well.

@bd5av8r1

3 ай бұрын

The 787 is totally electric. It's made that way. It fully needs 3 GPUs to function with no APU. Engines start Electrically as well. (has electric starters for engines as well)

@EstorilEm

3 ай бұрын

@@bd5av8r1I think you’re missing the entire point of his post - he knows it’s electric but is surprised just HOW MANY damn GPUs are required. Also they aren’t starters, they’re the generators that can revert function as starters.

@bd5av8r1

3 ай бұрын

If it turns the engines over, it s a starter as well. I see them daily here on position 3 here at work.

@andymelchor9950

Ай бұрын

It’s called a VFSG (variable frequency starter generator). Essentially yes it a generator, but also a variable frequency starter to apply the power for starting/spooling. 2 per engine 👍😁

Great video, I work at RR on the XWB line and sometimes across on the Trent 1000

@dennisvijverbergbrakesrele6098

8 күн бұрын

That's cool!

@markyyyyyyyy321

8 күн бұрын

@@dennisvijverbergbrakesrele6098 thanks, they sent me out to Airbus Toulouse to help provide on-wing care so that was really interesting. What is it you do?

B787 is mostly an all electrical aircraft where ii doesn't use bleed air to power its system but requires 2 ac power gpu to spin its engine when APU is inop.

@99domini99

3 ай бұрын

So it has electronic starters instead? That’s kinda wild, almost every aircraft I know of uses bleed air to spool up the engines.

@keithjurena9319

3 ай бұрын

​@@99domini99 With bypass ratio over 10:1, there isn't much excess HP air. Overall pressure ratio is 50:1. Starter motor is also a generator, providing anti ice and HVAC along with hotel loads.

@1v1qsns

3 ай бұрын

@@99domini99I believe they’re starters then become generators once start is complete

@andymelchor9950

Ай бұрын

Actually it requires 3 external sources for engine start :D

MSFS 2024 is off the chain!

Indeed, if both engines should fail, the RAT (Ram Air Turbine) is the last source of power together with the batteries.

How are the three GPUs synchronized with each other so that the AC outputs are all in phase?

@dennisvijverbergbrakesrele6098

3 ай бұрын

GPU’s are not synchronized, each will provide power to a separate circuit of the aircraft, these are isolated by the Bus Tie Relays. Then each will provide power to the common motor starter controller to provide power to the starter generator of the engine. Not sure about B787, but many two engines ETOPS aircraft don’t tie there busses to getter to equalize the loads during flight . At least it’s not done on the B777, it’s done on the B747 and MD11 for example. If you have an external power unit connected to the aircraft the aircraft uses what it gets. But it will try to match APU and or Engines generators to fase a frequency to make a non break transfer when GPU are selected off in the cockpit.

Interesting, I never expected generators to be the start cart instead of the overgrown leaf blower ones. And those are big generators, never knew an airliner consumed that much electrical power.

@user-vk4vd7vr5t

3 ай бұрын

Just to give you some idea the small gas turbine P&W APU on a 787 makes 450kVA of electrical power. Same as a 5 tonne diesel cummins generator.

@MandoMonge

3 ай бұрын

the 78 is a bleed less aircraft, so it's all electrical. using all 6 generators onboard (2 on the APU, and 4 on the engines) it can produce 1.45 MW of power

@stargazer7644

3 ай бұрын

It's the starter on the one engine taking most of that power.

@user-vk4vd7vr5t

3 ай бұрын

@@stargazer7644 787 APU and subsystems are actually able to start both engines simultaneously

I know that each cable-plug set has a max. capability of 90KVA. So I assume you would need 3ea of healthy 90KVA GPUs to perform the engine-start and not tripping?

@dennisvijverbergbrakesrele6098

3 ай бұрын

You need two 90KVA for engine start. We used three as the GPU were bad and we were trying to figure out which one. Normally with a third connected you can run the airco system

@andrewsoemantri2691

3 ай бұрын

@@dennisvijverbergbrakesrele6098 thank you very much for explaining.. I've experienced mixed performance with the newer generation TLD GPUs (like the ones in the video). Seems to me that the previous generation (mostly using Tier-2 Cummins or Deutz engines) are simpler and more reliable.

@supersnot4

3 ай бұрын

@@andrewsoemantri2691 We had a brand new one grenade a radiator fan about a year ago. It was only a month or two old at the time.

I remember when they were used on the 707‘s and DC-8’s.

@elliotepstein8074

3 ай бұрын

They were actually "huffers" in those days.

I'm curious as to whether or not it would have been possible for the 787 to have an air starter on the #2 engine as a secondary means of starting for such cases where the APU is inoperative. This would allow the #2 engine to start using the normal means of an air cart and then generate enough electrical power to start the #1 engine.

@dennisvijverbergbrakesrele6098

9 ай бұрын

That’s not the way Boeing went, no architecture on the aircraft to do that, the starter generators can do the job (even just one). You just need GPU’s that are reliable. Don’t think Boeing will add something like that ever, it’s would just be dead weight and will just be rarely used.

@lolvks

3 ай бұрын

It doesn't really solve the problem, you'll just be hooking up a bleed air cart instead of an additional GPU. You'd also end up with #1 and #2 engines being of different spec and a component that's not being used 99.5% of the time adding additional complexity and dead weight to the aircraft.

@mr.slowhand3843

3 ай бұрын

​@@lolvksthe whole aircraft is based on electricity as I know. No more bleed air and turbine drive AC compressors no bleed Air etc irs all electric. So the Generators work as starters as far as I now. So the whole pressure Air starter piping is not needed for saving weight and so on. It is a new generation of aircraft with the newest technology.

@lolvks

3 ай бұрын

@@mr.slowhand3843 correct. Engine starts are done exclusively using electrical power through the VFSGs (variable frequency starter-generator). The only thing bleed air is used on the 787 is for engine anti icing.

Wow. Good graphics.

@NightReaperSunDestroyerOfGods7

3 ай бұрын

Yeah, go outside.

How does the power output of each of those ground power units compare to the output of the APU on the 787?

@CrazyMrTim

3 ай бұрын

there's a minimum requirement of PSI the cart has to put out to be able to start the engines. It's always preferable to use the APU

@jcolbyt82

3 ай бұрын

@@CrazyMrTimThe 787 doesn’t use bleed air to start it’s engines. The generators on the main engines (2 gen/motors each engine) double as starting motors, starting them electrically. No bleed air system is used on the 787 at all. The a/c packs and pressurizations system uses electrically operated compressors. The wing parts that are normally heated with bleed air are electrically heated. My understanding is that the engine anti ice system utilizes bleed air but that’s it. There isn’t a bleed air ductwork system throughout the plane like on other airliners. The APU, as well as the engines, drives 2 generators to power the electrical system of the 787. The bleed air system was eliminated due to the huge decrease in efficiency that occurs from taking bleed air off of an engine. Less compressed air through the combustion chamber and turbine = less thrust. There’s also the added benefit of eliminating a potential source of cabin air contamination by not utilizing engine bleed air for pressurization and ventilation.

@CrazyMrTim

3 ай бұрын

@@jcolbyt82 Ah. My knowledge of the 787 is limited. I'm qualified on the CRJ, 737max, A320 family, and the 777, but we haven't had the 787 where i work

@ChristopherBurtraw

3 ай бұрын

No more than 1/3rd, apparently, since they needed 3 of them for a successful start lol

@sidv4615

Ай бұрын

@@CrazyMrTim do you still fly the triple? i had a few questions if you dont mind

What is protocol with INOP APU? Can you fly revenue flights with pax or not? I once had an AA 738 flight out of DFW and they started one engine while we were still at the gate and obviously before we were pushed back. I wondered if the APU was INOP on that plane. Cheers, thanks for sharing!

@dennisvijverbergbrakesrele6098

4 ай бұрын

Hello, you can flight without a working APU, depending aircraft, it can be inoperative for a certain amount of time, usually is a category C MEL item, and that is 10 days.

@bmwtravel1100

3 ай бұрын

yeah, I was once on AA flight at ORD where we had an air start on one engine at the gate. pilot told us what was happening, said "dont worry, once its running, its running"

@user-vk4vd7vr5t

3 ай бұрын

ETOPS is not possible with APU inop.

@paleghost

3 ай бұрын

@@user-vk4vd7vr5t i was on a BA 787 PHL-LHR with the APU inop. The captain said there was a lot of paperwork necessary. It was incredibly loud during the sTArt and it seemed it took a long time

@philiproseel3506

3 ай бұрын

Flights over land of up to 4-5 hours are ok, I believe. Anything of that duration over water is not. Airliners with inop APUs fly all the time. It’s one of the things that can be deferred on an aircraft until it can get to a maintenance base. Perfectly safe.

the older CF6s required the equivalent of 200hp of air power (at the starter) to start - im guessing these need a lot more!

@mlehky

3 ай бұрын

The 787 does not start with air, it’s use electric starter/generators.

@ghostrider-be9ek

3 ай бұрын

@ I did not say the 787 did, I said the cf6 required 200hp from the air starter, and no doubt these newer, larger engines require more (electric equivalent) power

@dennisvijverbergbrakesrele6098

3 ай бұрын

The same engine is on the B747-8, but then with the air starter. The same hugger that start the CF6 (but a lot faster ) will start the GEnx.

@barjan82

3 ай бұрын

The 787 is a different kind compared to other aircraft. It's main engine is started by two 250kVA AC starter-alternators, while other aircraft engines are mostly started by pneumatic power (bleed air) supplied by the APU or a ground cart. Starting the engine of the 787 takes a s*it load of electric power 🤐

@ghostrider-be9ek

3 ай бұрын

@@barjan82 yea I was expecting this! the old air starters were clunky, but light weight.

Why stop the engine once you've got it started? Was the initial start just to make sure it could be done before loading the aircraft?

@dennisvijverbergbrakesrele6098

2 ай бұрын

Crew didn’t want to board passengers until they would be confident the engine would start with the equipment we had connected.

A question if I may...what prevents a jet engine from starting to where it would take 3 GPU`s.?

@dennisvijverbergbrakesrele6098

4 ай бұрын

We had bad GPU’s they kept tripping during the start of the engines, after 3 GPU’s connected the engine finally wanted to start. Normally two 90KVA GPU connections should do the job, and with a third one you can run the airco packs.

@TheCarsche

4 ай бұрын

I guess I don't understand why the engines don't start w/o a GPU. Is that something exclusive to the 787. Aviation always fascinates me even the areas I don't understand. I worked for an airline but always on the customer service side. Thank you for understanding

@dennisvijverbergbrakesrele6098

4 ай бұрын

For starting the engine you need electricity, this is delivered by the Auxiliary Power Unit in the tail or by Ground Power Units. This aircraft had a APU that was inoperative, that why GPU ‘s are used to start the RH engine, once that one is working the power delivered by RH engine then starts the LH engine.

@priyam352

3 ай бұрын

@@TheCarsche the 787 doesnt use a bleed air system where other aircraft would need an airstart cart i think its called the 787 can use electrical enrgy from gpus to spin up one of the 2 generators per engine and start the engine that way but you need atleast 2 to do it and if they are unreliable a 3rd might be neccessary

@AllanFolm

3 ай бұрын

If you can't spin the compressor stage fast enough, there is not enough air through the engine to cool the burner cans, and you have a "hot start" which damages the engine. Once there is enough airflow, you can light off the fuel in the burner cans, which then accelerates the air from the compressor stage, providing airflow through the exhaust turbine, which in turns accelerates the compressor, providing more air, burning more fuel, generating more power in the exhaust turbine, and at a certain speed, the engine is self-sustaining and you can turn the starter off. It's all about the cooling of the burner cans.

These engines don’t have a pull cord for when the APU is OOC?? Our snapper riding mower (like Gump’s) had a starter motor AND a pull cord. Very handy…

@bd5av8r1

3 ай бұрын

No. at least since it does not you dont have to worry about it snapping :D lol

am really scared of people in this comment section thinking this is a simulator. Id love to know what they've seen to even think it is one.

@dennisvijverbergbrakesrele6098

2 ай бұрын

It flabbergasted me to🧐

Which sim was this done with?

@dennisvijverbergbrakesrele6098

3 ай бұрын

The real ☝️

@drforjc

3 ай бұрын

Would need to be a pretty good sim to show the scuff marks around the fuel cap at 0:51

did this on a CX+ lol in Chile - no aux apu - Rolls ae 3007 engines that didn't like starting without an external power source! disagreed with us heavily!

that alternator must be beefy AF to handle the current from 3 carts from a dead stop and not burn out.

@ZurOhki1

3 ай бұрын

You'd think so, but that's the same sort of power that a single motor Tesla Model 3 can consume when you put your foot down and that motor isn't very big.

@SupremeRuleroftheWorld

3 ай бұрын

@@ZurOhki1 the model 3 motor does not have to fly all day and is not watercooled. it physcially cannot be as large as a EV motor if it has to fit in the engine.

@haunter_1845

3 ай бұрын

​@@SupremeRuleroftheWorldTesla model 3 motors require a liquid cooling system. Think and research before you speak yeah?

@SupremeRuleroftheWorld

3 ай бұрын

@@haunter_1845 i know bloody well what i am talking about so take a step back and reconsider your comments before responding. and the starters in these planes DONT have liquid cooling but do have to handle more power in a even shorter burst than the motor in a tesla has to absorb.

Hello, no airstarter needed?

@austinlouvar5793

3 ай бұрын

787 is electric start. No bleed air on the aircraft for anything

ball park $500,000.00 replacement cost for the APU ?

@NeroontheGoon

3 ай бұрын

Not even close! A complete overhaul on its little brother the APS2700 is $717,000 dollars. The cost of the APS5000 is around $1.3 million dollars.

I assume they are not flying over ETOPS regions then...

@dennisvijverbergbrakesrele6098

3 ай бұрын

B787 is still ETOPS when APU is inop.

@user-vk4vd7vr5t

3 ай бұрын

@@dennisvijverbergbrakesrele6098 right, i assume the ETOPS rating is reduced though?

So I'm guessing the 787 needs only gpu for starting up the engines because it has no traditional air bleeding system. Am I right? Didn't know you would need 2 gpu's if the APU is inop to do it though. Glad to see a Spanish airline in the channel btw :) (Also an Iberia A330 on the next gate)

@tomstravels520

9 ай бұрын

Seems you need 3 by the looks of it

@surchris

9 ай бұрын

Boeing 787 All You must have a minimum of two external power sources to start the engine. You may use three external power sources to reduce the load shed in the cabin during right main engine start. Each external power source must have a minimum capacity of 90 kVA at 115 VAC. You cannot start the two engines at the same time if you use external power sources. If you have only two external power sources, they must be connected to the forward external power receptacles. If it is necessary to start both engines, it is recommended that you use the electrical power from the running engine to start the second engine.

@edmondhung6097

5 ай бұрын

@@surchrisDoes the running engine need to spool up to cross feed the other engine start?

@surchris

5 ай бұрын

@@edmondhung6097 Yes. With the one engine running, it now can start the other engine with the generators from the running engine. Electric Start, no bleed air used.....

@andymelchor9950

Ай бұрын

@@surchrisI can assure you the 787 will not start with 2 external power sources only. It must have 3 :)

You are indeed limited to 180 ETOPS.

I thought, the engines are only to start with air pressure?

@hyrrokinfamily

4 ай бұрын

On the 787 the starter motor is actually the alternator which is used as an electrical motor to power the engine until it is self-sufficient. After starting the electrical motor becomes the AC generator again

@dennisvijverbergbrakesrele6098

4 ай бұрын

Not on the B787, the have starter/generators on the engines.

@priyam352

3 ай бұрын

787 doesnt use the bleed air system of conventional aircraft it replaces all the systems with electrical ones so starting engines /anti ice / ac is all done with electrical power

I didn't realize the onboard APU generates more power than the ground GPU.

@dennisvijverbergbrakesrele6098

3 ай бұрын

Each APU starter generator it rate 225KVA

The GPU are DC or ac?

@dennisvijverbergbrakesrele6098

3 ай бұрын

115VAC 400HZ and should be 90KVA rated

@ezquimal

3 ай бұрын

@@dennisvijverbergbrakesrele6098 thanks

What was the point of this? you started the engine only to turn it off?

@simongreen9862

3 ай бұрын

I dunno man ask the guy who lived two doors down from our old house he seemed to do it a lot

@dennisvijverbergbrakesrele6098

3 ай бұрын

Yes that was the point of it all.

Really sucks not having the APU huh...

Is it safe when an aircraft engine does not start at once; 🤔

@dennisvijverbergbrakesrele6098

3 ай бұрын

Yes it is, you just need to take in account starter/generator duty cycles, you will have to wait 10 minutes after a start attempt if I am not mistaken.

@makisgggg838

3 ай бұрын

@@dennisvijverbergbrakesrele6098 Thanks!!!

Won’t the cones next to engine 6:46 get sucked inside ?

@dennisvijverbergbrakesrele6098

3 ай бұрын

Nope still to far away to get pulled into the engine at idle

Man, I would hate to work with heavies. I work with 320s all day and doing an air start, with a full flight, with an airstart, it's almot impossible to make a 40 minute turn. What's the minimum turn time for a heavy like this? 1 ground power connection and 1 air hose is all I really want to deal with xD

@dennisvijverbergbrakesrele6098

2 ай бұрын

Normal ground time are about 2 hours, some companies push it to 90 minutes if they arrived late. But then you want definitely a working APU.

Happens to me all the time when I plug in the coffee maker and toaster at the same time

You can't just ask a passing plane for a jump?

@dennisk5818

3 ай бұрын

Yea, can't you get a couple of guys to push the plane into the wind to start the engines? Works on my VW.

@dennisvijverbergbrakesrele6098

3 ай бұрын

Jumper cable would be long and heavy.

No APU !?!, No Go!

I don’t see a huff cart ?

@dennisvijverbergbrakesrele6098

3 ай бұрын

Not required for a B787, it an all electric aircraft.

you dont need APU air to start a 787. it has a starter generator.

Está flojito de aros😂

… never ride in a lemo that AC doesn’t work… what da?

Done this hundreds of times on A320 and 757..........always fun

@cjmillsnun

3 ай бұрын

Only you haven't because they use an air starter. The 787 is purely electric.

@Vulcancruiser

3 ай бұрын

@@cjmillsnun LOL........how long have you been building jets

@10293

3 ай бұрын

@@VulcancruiserDon’t have to build them to know how they function

@Vulcancruiser

3 ай бұрын

@@10293 Spent 38 years in airline ops......from local to global operations.......

@EstorilEm

3 ай бұрын

@@Vulcancruiser38 years in airline ops and you don’t know the ONE aircraft that’s famous for having no bleed air / fully electric start/anti-ice etc? …wow

GE engines are better. They have internaly an eletric engine that starts the main engine.

@dennisvijverbergbrakesrele6098

3 ай бұрын

Hello there, the GE engine has the same set up to start as the RR. Two starter/generators

@TianarTruegard

3 ай бұрын

Electric motors need power to operate. with the aircraft not running (APU not functioning), no power is being generated so its supplied by the external GPUs (Ground Power Units). As is noted in the video description, the aircraft's APU (auxiliary power unit) wasn't functional. Normally the APU provides electrical power when the 2 regular engines are not running. The APU is also used to provide the power needed to start the regular engines. Being smaller, the APU is much easier to start.

Totalmente falso cuando los motores estan operando dos luces rojas una en el fuselaje superior y otra en el fuselaje inferior dan indicación de operaciones de motores y aqui no se ven esas luces aplicadas ni tampoco estaría el personal caminando dentro del area de succión y expulsión de los motores

@dennisvijverbergbrakesrele6098

3 ай бұрын

Nothing made by a computer sim in this video, not really know how you would come to a conclusion like that.

Why didn’t you guys just airstart? That’s another option too.

@dennisvijverbergbrakesrele6098

3 ай бұрын

Not on the B787, it doesn’t have the bleed air architecture to drive an air starter. It only has two starter/generators on the engine.

@nicholasmohr1619

3 ай бұрын

@@dennisvijverbergbrakesrele6098 ah ok I see. I don’t work with stuff that new so I’m glad you said that. The biggest thing I’ve air started is a CRJ 200

@mgomez5606

3 ай бұрын

​@@dennisvijverbergbrakesrele6098no air cart capable?

@mgomez5606

3 ай бұрын

Once #2 engine starts it overrides the power unit?

@EstorilEm

3 ай бұрын

@@mgomez5606the one engine is way more than needed to start the other engine and power all the systems on the ground.

Seems dangerous to be that close to the engine.!

@dennisvijverbergbrakesrele6098

3 ай бұрын

Not dangerous it you know what you are doing

@ricks_talented_tongue

3 ай бұрын

It's fake from a simulator...

@cnvi08

3 ай бұрын

if that’s from a simulator I am impressed w the video quality!

This looks like a sim…

Yeah, I'm all set with never flying a Boeing aircraft again in my life. Airbus all the way, hell I'd rather fly a McDonnell Douglas MD-80 over anything Boeing is putting in the sky today.

@stargazer7644

3 ай бұрын

We're all impressed by your ignorance.

@acorredorv

2 ай бұрын

You know that the bean counters that created the MD-80 are the same ones that replaced the engineers at Boeing, right?

Lame.

Has anyone not realised this is from flight simulator

@ytzpilot

3 ай бұрын

Well now I do 😂

@mitseraffej5812

3 ай бұрын

Yes indeed, I doubt any aircraft operator would let someone wonder around their airplane filming, especially during engine start.

@psrpippy

3 ай бұрын

Of course it’s not. It might seem like it is but all his videos are genuine.

@markcardwell

3 ай бұрын

Wondered why nobody was there 😅

@psrpippy

3 ай бұрын

@@markcardwell but there are, you can see engineers in the background. He’s an engineer based in Miami. Flight simulator maybe realistic but it’s not this good yet. Look carefully, you’ll see engineers and ground staff.

This whole thing is fake. It never happened. It is computer generated #Dennis Vijverberg, the person who posted. I'm tired of these individuals posting this nonsense.

@dennisvijverbergbrakesrele6098

3 ай бұрын

Just wondering, how would you come to a conclusion that it is fake? Just through some other comments or is there something that is shown that is faked / unrealistic.

@joshb124

3 ай бұрын

Dumbest comment of the year

@MarsVinette

2 ай бұрын

@dennisvijverbergbrakesrele6098 I searched the internet for anything which came close to this story including the various aircraft investigation sites and found nothing

@dennisvijverbergbrakesrele6098

2 ай бұрын

@@MarsVinette the video isn’t related to any incident or accident. APU was just inoperative and deferred iaw MEL.

This is why the aircraft and the people who are assigned to crew them are garbage. Drive if you can.

en.wikipedia.org/wiki/Air_Europa#Current_fleet

@danners4302

9 ай бұрын

How’s about no

@CrazyForCooCooPuffs

9 ай бұрын

What was the point of your post?