How Jet Engines Work | Part 2 : Outputs

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  • เผยแพร่เมื่อ 22 พ.ย. 2024

ความคิดเห็น • 178

  • @АлакПатрова
    @АлакПатрова 2 ปีที่แล้ว +81

    I'm a diesel mechanic. Have been for 15 years and always wondered how turbine engines work and how the compressors did their job and the stages of them. This really helped.

    • @darrylwmurphy738
      @darrylwmurphy738 ปีที่แล้ว

      If you want to know more about jet engines? You want to check out Aircraft Science - this will give you an insight on how jet engines are built, tested and how they are "Started"
      There's two kinds of jet engines
      Airlines
      Fighter jets
      I'm taking diesel mechanics
      Do you remember basic theory of the steam engine?

    • @darrylwmurphy738
      @darrylwmurphy738 ปีที่แล้ว +1

      Also jet engines are different from diesel engines and a different application. Similar
      Diesels do require that fuel have to be primed before starting especially for locomotives. Just like for lawn motors (gasoline) have to be primed too prior to starting.
      But in jet engines uses duel ( JP) which can be JP-20, JP-30 up
      Fuel still have to go a fuel filter before the fuel pump to strain out any particles .

    • @darrylwmurphy738
      @darrylwmurphy738 ปีที่แล้ว

      I want share if you already about the turbocharger and the Exhaust Gas Recirculation and it's blowers
      Turbocharger also has a frequency.

    • @akhilvijay8670
      @akhilvijay8670 ปีที่แล้ว +1

      Still I didn't get completely

  • @TC-BCN
    @TC-BCN 3 ปีที่แล้ว +53

    Part 1 helped me to pass aircraft general knowledge course in atpl exams, great animation and narrative, helped me a lot, thank you so much for the video and appreciated.

    • @StClair-gt8qg
      @StClair-gt8qg 10 หลายเดือนก่อน

      PPP 00 pp p puppy 0😮😅😅😅😅😅😅😅😅😅😅😅😅

    • @StClair-gt8qg
      @StClair-gt8qg 10 หลายเดือนก่อน

      😅

  • @skyediamonds5654
    @skyediamonds5654 ปีที่แล้ว +4

    This is an absolutely great detailed video. Highly recommend for anyone interested in jet engine operation of airliners as the Boeing -777.
    Thank you very much!!

  • @Greatdome99
    @Greatdome99 ปีที่แล้ว +34

    In case anyone wants to know how the generator stays at constant rpm, the 'constant speed drive' has a hydraulic pump powered by the engine G/B which powers a 'swash plate' piston engine (like your car's AC pump). As N2 speed changes the hydraulic pump increases flow/pressure, causing the angle of the swash plate to change, keeping the output at a constant rpm.

    • @friedchicken1
      @friedchicken1 ปีที่แล้ว +1

      wow tenk yu i was just wondering that

    • @b43xoit
      @b43xoit 10 หลายเดือนก่อน

      Interesting design choice vs. an electronic solution as used for the backup alternator.

  • @marcoacerbi3647
    @marcoacerbi3647 ปีที่แล้ว +2

    Sono un meccanico italiano,e devo dire che la grafica e ottima e molto chiara e intuitiva,bravi!!

  • @Ravi-ts2kx
    @Ravi-ts2kx ปีที่แล้ว +4

    This is so helpful. I'm a visual learner, and reading or seeing just some pictures alone don't really do the trick for me. These videos are a good visual representation of the procedures order for jet engine operation. Thanks a lot!

  • @neromah
    @neromah 3 ปีที่แล้ว +30

    What an insanely detailed and well drafted video by Aircraft Science, nothing much to say about the video, simply put, ABSOLUTELY INSPIRING! ✈️🌟

  • @aircrafter7505
    @aircrafter7505 11 หลายเดือนก่อน +1

    It's marvellous how engines are made

  • @Greatdome99
    @Greatdome99 ปีที่แล้ว +4

    Bleed air comes from the 9th stage at idle (50% N2), switching to the 4th stage at cruise (100% N2). FAA regs require bleed air to stay below 450F (auto ignition temp of fuel) so it's always run thru the intercooler, cooled by fan air.

  • @dsarnes7
    @dsarnes7 ปีที่แล้ว

    This series has saved me so much time from reading my Boeing 777 owner's manual

  • @lawan8025
    @lawan8025 2 หลายเดือนก่อน

    this video helped me to pass my flight exam for a private pilot licence. Thank you❤

    • @AircraftScience
      @AircraftScience  2 หลายเดือนก่อน

      Glad it helped!

    • @kendrocool
      @kendrocool หลายเดือนก่อน

      bro r u flying Jets for a PPL?

  • @billyost1479
    @billyost1479 ปีที่แล้ว

    As an turbine engine repairman for helicopter and fixed wing prop aircraft... I'm addicted to this.

  • @aviationalphabet6193
    @aviationalphabet6193 2 ปีที่แล้ว +3

    Sir, you are simply awsome. Can't stop to praise you. Your animations helped me a lot to understand. Thank you

  • @GreyBearcub
    @GreyBearcub 10 หลายเดือนก่อน

    I really want to know the background melodies you have used, it makes the whole video and animation feel epic and majestic! This series is by far one of the best found in TH-cam and the channel has much potential. I hope success is always with you, keep up the good work!

    • @AircraftScience
      @AircraftScience  10 หลายเดือนก่อน +1

      "Go big or go home" is the title of the background track. It's available in the Wondershare Filmora audio library.

    • @GreyBearcub
      @GreyBearcub 10 หลายเดือนก่อน

      @@AircraftScienceThank you very much, I hope to see more of your fine work!

  • @yourpapa5567
    @yourpapa5567 2 ปีที่แล้ว +6

    Awe inspiring and detailed! Much appreciated for the video!

  • @erdum
    @erdum ปีที่แล้ว

    I have flown aircrafts in simulator and I also know technical details about how systems works but always wondered to learn in depth and in your video you just blown my mind and you have satisfied my knowledge crave. Hats off to you man❤

  • @one.darkstar
    @one.darkstar ปีที่แล้ว +3

    Awesome videos, and the music wow. I'm a mechanical engineering student and am always fascinated by evolution of technology. Watching this video made me realize that its a wonder how humanity has achieved so much and continues to push further. So many components, so much complexity and prone to failures, and making it all work at once! And you showing it all beautifully with an exciting music. Thank you for your work. Subscribed.

  • @CHOXON2CHOXOFF
    @CHOXON2CHOXOFF 3 ปีที่แล้ว +3

    Amazing explaination with amazing animation. Easy to understand

  • @deansnipah1392
    @deansnipah1392 ปีที่แล้ว +1

    Usually there are 2 stages of pneumatic bleed air. The lower stage, lower temp/pressure is used to climate control and keeping the plane pressurized. The higher stage of compression uses high temp/pressure bleed air only for anti-ice systems.

  • @wattsmichaele
    @wattsmichaele 2 ปีที่แล้ว +2

    This is alien tech….no joke

  • @Mechanic779
    @Mechanic779 2 หลายเดือนก่อน

    I love watching your videos very easy learning thank you soo much

  • @alphadeltalosmartineztech.6542
    @alphadeltalosmartineztech.6542 3 ปีที่แล้ว +2

    part 1 and 2 helped me a lot thanks a lot

  • @faganfit572
    @faganfit572 ปีที่แล้ว

    What an amazing aircraft. But what an even more amazing animation and explanation. Wish I had something like this for my own aircraft (ATR). Great work man.

  • @satyaranjanbehera1538
    @satyaranjanbehera1538 3 ปีที่แล้ว +1

    The animation is really awesome.. Please make more video on GE 90 and B-777 aircraft.

  • @sorgfaeltig
    @sorgfaeltig 2 ปีที่แล้ว +8

    At time 1:41 there is an ERROR. The aircraft electrical systems don't work at 415 Hz. They work at 400 Hz. Probably the creator of this video mixed the "15" from the voltage of the 3-phase electrical system which is 115 Volts phase to neutral, whis is 200 Volts phase to phase.

    • @eddievhfan1984
      @eddievhfan1984 ปีที่แล้ว +1

      I was wondering about that; 400 Hz being the standard for air/sea "shore" power, I would figure most external power units would never be able to sync if that was the case.

    • @sorgfaeltig
      @sorgfaeltig ปีที่แล้ว +1

      @@eddievhfan1984 The external ground power units are designed to provide 115V/400V 3-phase 400Hz 75kVA. There is no need to "SYNC". The aircraft switched either to external power OR internal power. The sychronization of the 400Hz power is only performed when the two generators from engine #1 and engine #2 are switched to parallel mode.

    • @eddievhfan1984
      @eddievhfan1984 ปีที่แล้ว

      @@sorgfaeltig I was aware of that; what I meant was that if the IDGs ran off of 415 Hz (as claimed by the video) instead of 400, then when external power was provided to the aircraft, the GPU would simply trip its breakers due to not being frequency-synchronized; essentially a proof by contradiction/absurdity. And in any case, my understanding was that external power is paralleled with the other sources on the bus for load-sharing to minimize stress on equipment when transferring between sources, as opposed to a hard switch.

  • @leandrobustillosfernandez
    @leandrobustillosfernandez 2 ปีที่แล้ว

    EXELLENTEXCELLENT PRESENTATION IN DETAIL.

  • @traveladventuresandfoods.6195
    @traveladventuresandfoods.6195 ปีที่แล้ว +1

    Hello. I am an electrical engineer and work on turbo compressors. I watched part 1 and 2 of your video with great interest. These are best 2 videos on jet engines, I have ever seen.
    One question about electric generator attached to the engine. Why this is designed on frequency of 415 Hz. ? I have never heard of 415 Hz frequency. It is most commonly 50 Hz in Asia and Europe and 60Hz in America and Canada. What are the voltage then?

    • @AircraftScience
      @AircraftScience  ปีที่แล้ว +2

      Hi, I've made an error in the video; the frequency is 400 Hz. Airplanes use 115 volts, 400 Hz power because it reduces their total weight.
      The higher frequency reduces the size of electrical components (transformers, generators, and motors).

    • @traveladventuresandfoods.6195
      @traveladventuresandfoods.6195 ปีที่แล้ว

      @@AircraftScience Thanks very much. That is great information foe me.

    • @AircraftScience
      @AircraftScience  ปีที่แล้ว

      @@traveladventuresandfoods.6195 My pleasure!

  • @UmrzoqXayitboyev
    @UmrzoqXayitboyev 4 หลายเดือนก่อน

    Perfect work

  • @anthonyf.9170
    @anthonyf.9170 ปีที่แล้ว

    Excellent video and tutorial. 👍

  • @b43xoit
    @b43xoit 10 หลายเดือนก่อน

    "A bad weather condition" is exactly the same thing as "bad weather", but requires more words to say and hear.

  • @0304conde
    @0304conde ปีที่แล้ว +2

    Great video, just to mention that the IDG output is 400hz and not 415hz.

    • @Greatdome99
      @Greatdome99 ปีที่แล้ว

      Yes, 400 Hz, three-phase AC.

  • @praveenshetty2066
    @praveenshetty2066 3 ปีที่แล้ว +2

    Very informative video, nice work👍

  • @10msivana
    @10msivana 8 หลายเดือนก่อน +1

    Better make sure you don't shut down the right engine incase the left engine has a bird strike, or else its a 70 ton glider

  • @privskorp.9865
    @privskorp.9865 2 ปีที่แล้ว

    Thanks thanks thanks for these masterpiece

  • @gouthambalu3795
    @gouthambalu3795 3 ปีที่แล้ว +2

    Super bro exilanted 👌👌

  • @tonybarnes3658
    @tonybarnes3658 ปีที่แล้ว

    This is brilliant!!! How good are the people who design, manufacture,and service these incredible pieces of technology??!! This is mind blowing!! Strewth, how complex must the systems be in UAP/UFO/whatever the new acronym type vehicles?!

  • @mrkc10
    @mrkc10 2 ปีที่แล้ว

    Excellent video

  • @admensch
    @admensch 3 ปีที่แล้ว +1

    WONDERFUL 💫

  • @Golasoooooo
    @Golasoooooo ปีที่แล้ว

    This is very helpful

  • @rfd87
    @rfd87 ปีที่แล้ว

    Thank you very much

  • @bigredc222
    @bigredc222 ปีที่แล้ว

    Very good.
    Thank you.

  • @dilandias4018
    @dilandias4018 10 หลายเดือนก่อน

    It's very useful video....

  • @imnbsp
    @imnbsp 6 หลายเดือนก่อน +1

    now I can finally operate my jet engine before going to sleep

  • @khamnei
    @khamnei 2 ปีที่แล้ว

    Amazing visuals well done

  • @brauliorendonmancilla6633
    @brauliorendonmancilla6633 2 ปีที่แล้ว

    Thanks for you information, congratulations.

  • @ذيبذيب-س2و
    @ذيبذيب-س2و 3 ปีที่แล้ว +1

    This video is very cool

  • @Berlin-Ost
    @Berlin-Ost 3 ปีที่แล้ว

    Great job, thanks!

  • @raymondzhao9557
    @raymondzhao9557 2 ปีที่แล้ว

    this video is gold!

  • @marciomedeiros1173
    @marciomedeiros1173 3 ปีที่แล้ว

    Excellent!

  • @ks438
    @ks438 2 ปีที่แล้ว

    Awesome job!!!!

  • @MRWIRUPONGSUKARUJI
    @MRWIRUPONGSUKARUJI 2 ปีที่แล้ว

    ผมรู้วิธีการจุดระเบิดจากเครื่องยนต์เครื่องยนต์ แล้วครับ ครูไม่ต้องไปปรับเปลี่ยนอะไรเลยครับแค่สร้างที่ครอบยื่นออกมาแล้วก็สร้างที่ปิดเปิดเหมือนช่องระบายอากาศ วิธีการนี้วิธีเดียวครับที่จะทำให้ จุดระเบิดจากเครื่อง ยนต์เจ็ท ได้ครับ

  • @hen-hensuhendard5996
    @hen-hensuhendard5996 2 ปีที่แล้ว

    SUNGGUH SANGAT MENAKJUBKAN .

  • @therayanmusic4240
    @therayanmusic4240 2 ปีที่แล้ว

    Thank you.

  • @jaiyp77
    @jaiyp77 3 ปีที่แล้ว +1

    I'm so excited to see your next video, Do you have any other channels I can follow your progress?
    .
    Love you😍😍😍

    • @AircraftScience
      @AircraftScience  3 ปีที่แล้ว +1

      Hi, this is the only channel I have.

    • @jaiyp77
      @jaiyp77 3 ปีที่แล้ว

      @@AircraftScience Facebook, IG, twitter, etc.

    • @AircraftScience
      @AircraftScience  3 ปีที่แล้ว +1

      Currently I have nothing on the platforms you mentioned. Will let you know if I come up with something.

    • @jaiyp77
      @jaiyp77 3 ปีที่แล้ว

      @@AircraftScience OK^^

  • @anarabbasov5910
    @anarabbasov5910 2 ปีที่แล้ว

    This is really helpful and awesome video

  • @denizturan5940
    @denizturan5940 3 ปีที่แล้ว

    Thanks for sharing. I waiting for B787 Gnx 1B Engine opetation impatiently

  • @demal1010
    @demal1010 ปีที่แล้ว

    My question is how does the constant speed drive, drive at constant speed? Is it using something like an automatic transmission with a planetary gear set?
    Also you said the electrical systems needs two sources to run everything, but I've seen the apu alone run everything, for example during pushback before engine starting

  • @tuncaypekdemir7131
    @tuncaypekdemir7131 2 ปีที่แล้ว

    Awesome , many thanks 👏👏

  • @andreizadasilvapereira5312
    @andreizadasilvapereira5312 2 ปีที่แล้ว

    Part 1 is a perfect video to start a 777 in cold and dark

  • @hrishikeshdesurkar10
    @hrishikeshdesurkar10 7 หลายเดือนก่อน

    Can someone please explain how the air from the high pressure compressor is hot enough for the anti icing system ? It collected from before the combustion chamber

  • @cesarmatiasbalderrama3658
    @cesarmatiasbalderrama3658 ปีที่แล้ว

    Buen video

  • @ea-13
    @ea-13 3 ปีที่แล้ว +1

    Your video is amazing and very beneficial for everyone who wants to learn engine and aircraft. Which program do you use to visualize aircraft’s engine ? I want your permission to download your videos.

    • @AircraftScience
      @AircraftScience  3 ปีที่แล้ว +1

      The animation was done using the blender software. You can download the videos for educational purposes.

  • @anassule6468
    @anassule6468 11 หลายเดือนก่อน

    Lovely

  • @NaseerKhan-xb8iw
    @NaseerKhan-xb8iw 6 หลายเดือนก่อน

    if the right engine is also producing power then the right bus will be getting power from the IDG mounted on right engine instead from APU. am i correct?

  • @byantara2227
    @byantara2227 3 ปีที่แล้ว +1

    Damn youre so good, love it👍🏻👍🏻. Can you also make for boeing 737?

    • @AircraftScience
      @AircraftScience  3 ปีที่แล้ว +1

      Thanks for the suggestion. Will consider it after I'm done with the B777 series.

  • @Golasoooooo
    @Golasoooooo ปีที่แล้ว

    Please do more

  • @coolfreaks68
    @coolfreaks68 ปีที่แล้ว

    *At **6:00** - the engine starts powering the pneumatic actuators and the background music changes.*

  • @shoaibsial4288
    @shoaibsial4288 3 ปีที่แล้ว

    please have request to make videos on B777 ATA 31 and ATA 45. Thanks

  • @x-gamessimulator1067
    @x-gamessimulator1067 3 ปีที่แล้ว

    Good

  • @badman0078
    @badman0078 3 ปีที่แล้ว

    Nice👌👌👌

  • @Fernandodcj
    @Fernandodcj 2 ปีที่แล้ว

    What’s the temperature inside the combustion chambers at max power? How it walls doesn’t melt? Anything to cool its walls? What are the fuel injectors made of?

    • @Grouuumpf
      @Grouuumpf 2 ปีที่แล้ว +3

      Hot. Like, hot enough to melt steel, with some margin. But! That's only for the core. The combustion chamber is in two parts, the outer one is airtight but the inner one, where the flame is, is perforated to have a layer of fresh air between the wall and the flame, and to keep supplying more air to mix with the unburnt gasses.
      *Can* be made of some steels, though I believe it's usually a titanium alloy

    • @АлакПатрова
      @АлакПатрова 2 ปีที่แล้ว

      All good questions. I've wondered the temp difference of that against a diesel engine under boost.

    • @eddievhfan1984
      @eddievhfan1984 ปีที่แล้ว +1

      It's also worth mentioning that for control of engine temperature, the fuel/air mixture is significantly leaner than that found in internal combustion engines, as running a jet engine at its most optimal stoichiometric (full-burning) ratio generates enough heat to melt the engine. So there's a lot of excess air on hand to provide cooling.

  • @x-gamessimulator1067
    @x-gamessimulator1067 3 ปีที่แล้ว

    1:10 What is the name of the background song? I liked it a lot and it fits a lot with the video...

    • @AircraftScience
      @AircraftScience  3 ปีที่แล้ว +1

      The background music is called Go big or go home, it's from the Filmora stock library.

    • @x-gamessimulator1067
      @x-gamessimulator1067 3 ปีที่แล้ว

      Thank you🙂

  • @josephjeno6709
    @josephjeno6709 ปีที่แล้ว

    How engine combustion blades are cooled

  • @MrFrediou
    @MrFrediou 2 ปีที่แล้ว +1

    Thank you good video! The music is distracting.

  • @thegallantsaint2034
    @thegallantsaint2034 2 ปีที่แล้ว

    Now I understand why jet engines are covered in “spaghetti” pipes.

  • @candidochaves6980
    @candidochaves6980 3 ปีที่แล้ว

    Amazing🤘🤘🤘🤘

  • @dilandias4018
    @dilandias4018 10 หลายเดือนก่อน

    Please make the same video B787

  • @Tasty_Nuggets2327
    @Tasty_Nuggets2327 ปีที่แล้ว

    “Your going to obey me” are you kidding me

  • @kailashsingh9737
    @kailashsingh9737 ปีที่แล้ว

    Very beautiful sweet

  • @SsenyonjoSimon
    @SsenyonjoSimon 11 หลายเดือนก่อน

    What softwares do you use sir

    • @AircraftScience
      @AircraftScience  11 หลายเดือนก่อน

      Blender for animation and Filmora for video editing.

  • @alanwright5492
    @alanwright5492 10 หลายเดือนก่อน

    Isn't the 415 figure voltage, and not hz?

    • @AircraftScience
      @AircraftScience  10 หลายเดือนก่อน +1

      The aircraft power systems operate at 115V and 400Hz.

  • @jeanclaudelavallee4919
    @jeanclaudelavallee4919 2 ปีที่แล้ว

    what choosing 415 hertz power supply ? why specifily 415 hertz ?
    easier to filter ?

    • @AircraftScience
      @AircraftScience  2 ปีที่แล้ว +1

      A higher frequency (415 Hz) helps reduce the weight of heavy electrical components on the aircraft.

  • @fatihkunduz38
    @fatihkunduz38 2 ปีที่แล้ว +2

    115 V 400 Hz
    Not 415 Hz...

  • @billsmith7320
    @billsmith7320 ปีที่แล้ว

    I got a idea try a prop.

  • @revinot
    @revinot ปีที่แล้ว

    If this was a class i would fail

  • @scottl.1568
    @scottl.1568 ปีที่แล้ว

    Yeah that's right

  • @darrylwmurphy738
    @darrylwmurphy738 ปีที่แล้ว

    Similar to Energy Bleeding

  • @itsotechai
    @itsotechai 3 หลายเดือนก่อน

    ❤❤❤❤❤

  • @TrongNguyen-dv1ir
    @TrongNguyen-dv1ir 2 ปีที่แล้ว

    Các em nghĩ là cái gì chứ là những quả bit tong nổ và sả lực đẩy mạnh và những cánh quạt nó quay

  • @michaelharrison2775
    @michaelharrison2775 ปีที่แล้ว

    Something thrusts the veins which in turn

  • @TrongNguyen-dv1ir
    @TrongNguyen-dv1ir 2 ปีที่แล้ว

    Đâu phải là phi công giỏi nhất là có thể hiểu biết được hết tất cả đâu nhìn thấy cũng chưa chắc đã hiểu biết được để rồi nói là bộ phận máy cũng chưa chắc đã rành

  • @audreytan-l5o
    @audreytan-l5o 10 หลายเดือนก่อน

    Why is it 415Hz instead of 400Hz?

  • @jerry-rw4zq
    @jerry-rw4zq 2 ปีที่แล้ว

    What software u used?

  • @JoeyLovesTrains
    @JoeyLovesTrains 2 ปีที่แล้ว +2

    Why 415Hz?? Did you mean to say 415 volts? Because if it was a 415Hz generator, it would need to go through a ac-dc-ac transformer in order to power cabin entertainment, due to the fact that all outlets are 50/60Hz

    • @AircraftScience
      @AircraftScience  2 ปีที่แล้ว +2

      Yes, the generator gives 415 Hz output. An in-seat power supply (ISPS) converter changes 415 Hz to 60 Hz for the power outlets.

    • @JoeyLovesTrains
      @JoeyLovesTrains 2 ปีที่แล้ว +2

      @@AircraftScience why does it supply 415Hz? Are you aware of any specific reason it can’t just be a regular 50Hz or 60Hz generator?

    • @AircraftScience
      @AircraftScience  2 ปีที่แล้ว +6

      A higher frequency (415 Hz) helps reduce the weight of heavy electrical components on the aircraft.

    • @JoeyLovesTrains
      @JoeyLovesTrains 2 ปีที่แล้ว +1

      @@AircraftScience ohhh that’s super cool!

    • @sorgfaeltig
      @sorgfaeltig 2 ปีที่แล้ว +2

      @@AircraftScience NO, the generator does NOT give 415 Hz output. It gives 400 Hz output. The outlets for the passengers are only a minor unimportant part in the entirety of the electrical aircraft system. It is an on-essential system that has its own converter to convert the 115V 400Hz power via rectifiers and converters to "household devices-compatible" 115V/60Hz or 230V/50Hz

  • @x-gamessimulator1067
    @x-gamessimulator1067 3 ปีที่แล้ว

    1:10 What music?

  • @loxy4239
    @loxy4239 8 หลายเดือนก่อน

    Does anyone know what music this is?

    • @AircraftScience
      @AircraftScience  8 หลายเดือนก่อน

      Go big or go home (Filmora stock library).

  • @mysticwine
    @mysticwine ปีที่แล้ว

    It's essentially a diesel on steroids...

  • @jerrywatt6813
    @jerrywatt6813 ปีที่แล้ว

    Good luck to you young folks going for you're a&p license ' just study twice as hard as you think you need to that's what I did and you will pass you're pas you're exams with ease ' my boss said about my license remember it's a license to learn ! You will never know it all be safe and when jn doubt get help !

  • @TrongNguyen-dv1ir
    @TrongNguyen-dv1ir 2 ปีที่แล้ว

    Nhìn thấy cũng phải hiểu rõ ràng và phải biết cách làm việc chứ không phải nhìn thấy cái nói lung tung

  • @robertmbugua4691
    @robertmbugua4691 8 หลายเดือนก่อน

    Mi too