Boeing 747 Reverse thrust operation

Hello! How do you do everyone. Today’s video is about 10 minutes long and I hope you will watch it through to the end. I know that the majority of people can only handle 2-3 minutes before moving on but I assure you that you will not be bored if you are an aviation enthusiast 😀
The video today teaches about what happens externally at the engines when a pilot selects reverse thrust. Then I show you what goes on in the cockpit to make those things happen. Most modern large jet aircraft have thrust reverse systems to aid with aircraft deceleration after landing or in a rejected takeoff. Some an even use reverse thrust to back up the aircraft (not authorised on B747). On some engine types, reverse thrust is selectable in flight- usually just before touchdown. The important thing to note is that reverse thrust is all about the direction of the thrust. The engine does NOT start spinning in a reverse or opposite direction! All that happens is that the thrust that would normally be pushing the aircraft forward via the exhaust, is redirected forward in an opposite direction to the aircraft direction. This results in aircraft deceleration- similar to what boats do. They redirect the water forward as they approach the docking point to slow down. I have the usual captions of course and I do my best to indicate what is going on- have a watch and I hope you like it. At the end, see if you can recognise when the pilot selects reverse thrust after touchdown- enjoy!
‘Chi Di Gin! Later!😀✈️✈️✈️✈️

[@Biggles2498]

Finally an excellent video Explaining Reverse ESPECIALLY explaining Reverse Thrust Levers. None of the other Aviation Sites would do this. Thank you Sir.

[@Maersky-747]

I watched this video from Obet 3 times. The first time it was interesting to watch. The 2nd time I learned from it ... and I had to watch the video again for the 3rd time as I just love the way Obet explains things. The man is Captain Obet ... King of the Sky 🌟🌟🌟🌟🌟 ✈✈✈

[@pilot_obet7815]

Cheers- thanks

[@pilot_obet7815]

It deploys faster when armed. If not in use in flight it is down unless needed for use as speed brake.

[@Rwalt61]

@@pilot_obet7815 I'm not a pilot just an aviation enthusiast but I'm glad I found you. You are a wealth of knowledge.

[@ADIRU22]

@@pilot_obet7815 yes bro you're a very good teacher

[@paulchambers6657]

Obet if I wasn’t a half blind and half knackered 54 year old I’d be checking out flight school right now, you’re videos must be an inspiration to anyone who watches them, keep it up Captain 😀

[@pilot_obet7815]

Thanks 😊

[@rpyka1]

Thank you for this very thorough explanation of how the reverse thrusters work. I'd always been curious what lever does what and how when watching landing videos...now I understand 😀

[@abdhullahahmadh6078]

As usual, right to the point and beyond. Sir, the way you teach will make desktop and real pilot training a lot easier, it just sticks like glue. Thank you.

[@pilot_obet7815]

My pleasure

[@sebinamuwanga]

Thanks for the video, Skipper. I have always noticed and known about the engine sleeves/louvers but did not know about the blocking mechnism in the nacelle. Many years back when I took my first flight on a 707 from Entebbe to Gatwick, I asked my father why the engine sound increased after landing. He told me that, "the pilot increases thrust just in case there is something on the runway, or the aircraft fails to brake and he has to get airborne to avoid a run way excursion". Well he did not use excursion, that is my word, but that is what he thought happened. I believe up to this day, many people think the same way. The mechanical linkage is an ingenious way of ensuring that reversers are not deployed during flight. I have seen clips of U.S.A.F using reverse thrust (C-17) during approach to make them come in at a steeper angle. I wonder how that feels...

[@wilbisson1306]

Top notch explanation of the speed brake and reverse thrust ,understand it completely Captain , thank you for such a clear explanation all the best Wil !

[@amandaholden1362]

Thanks for taking the time to show us up close!

[@B747-4OO]

Great to see that blocker door mechanism close up!! Thanks a lot for this comprehensive overview! 😃

[@kd7alt]

My father and I used to watch plains land at pPDX Airport when I was a child. I have seen many different reverse thrusters from cowl slide to clam shell type. My father worked for Boeing

[@davebrown1409]

Again Captain I echo previous comments, to see closeup how the mechanism actually works internally was fantastic, we have no doubt all see the external mechanism working, but not the internals. Looking forward to your next clip !

[@mrkc10]

-400 & -8 when reversers come on certain segments of the leading edge slats retract…then redeploy after cancelling the reversers…pretty cool Boeing Design.

[@sebinamuwanga]

Great observation. May be the Skipper can explain the logic behind this.

[@ImperrfectStranger]

@@sebinamuwanga To help reduce the damage to the leading edge flaps. Reverse thrust pummels the flaps.

[@k0wdm144]

Awesome description of reverse thrust. Thanks for this!

[@ryanhell921]

I just love your videos Captain! And I'll never forget the 1st time I rode a 747, 1981, Pan Am, to Tegel West Berlin, my very first ride to Germany after I joined the U.S. Army! Was in December that year and will never forget. Was snowing that night and will never forget the 'follow me truck' that pulled outside my window after we landed. I really enjoy your videos and have always loved the Boeing 747

[@elenacolon3880]

hi captain great explanation of reverse thrust plus speed breaks just fantastikkkk

[@mrnice5245]

Thanks you for putting your time into these videos! I always wondered how the Reversers on an airplane worked. And now I know because of your videos!! Thanks captain Obet :)))))

[@elenacolon3880]

thank you captain great view of thrust reverse , fantastikkkk

[@DAviation179]

Love this guys voice, he sounds like James Earle Jones

[@kitburns1665]

Excellent! Appreciate the description of the interlocks and operation of controls. Nice!

[@forbyf5938]

Great description of the system

[@ronaldcuieii4775]

I like the reverse thrust option. That was sharp to see that up close. Something's gotta give for Boeing to keep the 747 going. Very very nice. Please keep coming out with more vlogs!!

[@n6mz]

Fantastic, Captain. Thank you. Look at that sky --- I can remember when Hong Kong had clear air and great views.

[@henrivanbemmel]

Thank you very much for this video. I thought that the system knew it was on the ground because the aircraft weight was sensed by the landing gear. You suggest that the interlocking system knows it is down by the deployment of the spoilers. There could be care situations where the spoiler may not be used. Thank you for your time.

[@n1msu]

Thank you and the airline and whoever was up in the cockpit putting engine into reverse config. I've seen many many aviation technical videos but never seen a demo like this! It's great to see some original unique content here on youtube which isn't easy with the amount of aviation videos posted here!

[@pilot_obet7815]

Thank you.

[@jayakumarn]

Thank you for explaining this in detail. Really informative.

[@BigPops757]

You the man captain. Pretty cool how you teach us how the instruments work.

[@captainzeppos]

good lord, all these years I thought that when enabling thurst reversers you also have to push thrust levers forward, had no idea you just keep them in idle the whole time after nose wheel touchdown and then you simply pull up the reversers. this is why the bloody thing could never break in MSFS

[@elenacolon3880]

thank you captain, automatic selections systems, happy flying

[@charlesalves5367]

Thanks very much captain Obet, you gave me an insight about aviation. 👍👍👊👊💯🇬🇾

[@annapaolagrandini1052]

Once again fantastic explanation as usual ... thank you Captain

[@Boze0415]

Thanks so much. This clears up a question that I have always pondered. Also thanks for the demo with the engines.

[@hasiemildiallo4468]

Formidable! Super vidéo. Merci.

[@chrisnizer5702]

Jet engines...doesn't get much cooler than that! Thank you for the video my friend, good stuff. 👍👍

[@KeunMikeun]

Excellent as usual. Thanks so much, Captain.

[@jaybee9269]

Straight up BRILLIANT video, mate! Very clear explanation. Well done!

[@pilot_obet7815]

Thank you Sir

[@markcardwell]

Thx Capt

[@frankthomas855]

Thanks for a very informative and entertaining video.

[@rayoshroff4558]

Absolutely superb 👍

[@johnbrown-rm8kc]

great video thanks

[@Wanderns]

You are The Best!

[@Kenny-en7wb]

This is so good!

[@alfiesycip6920]

Thank you for this wonderful video sir! Very educational, particularly to a guy who loce 747 like me 😁

[@ashwinraghunath]

Superb video, Captain. This is the kind of content that is invaluable in so many ways. :)

[@adamluke1289]

Love your videos!

[@pilot_obet7815]

Thanks

[@thestormchasingconcorde6184]

reverse thrust can only be applied on the ground, except if you're flying a DC-8 and the ejectors are out

[@user-bx7nw1ve6y]

I'm old enough to recall a Delta DC8 flight into LAX during the seventies where the inboard engines were placed in idle reverse during the initial approach phase, long before landing. There was a bit of minor shuddering, but a PA had been made, warning the cabin occupants well in advance that the procedure would be performed. I guess you don't do that any more.

[@jeanhuysse1227]

Wonderfull Captain! Thank you very much for show us!

[@pilot_obet7815]

My pleasure

[@gerardmoran9560]

Great video! Interesting fact- the DC-8 series 60 & 70 (perhaps earlier ones) and the USAF Lockheed C-5 don't have flight spoilers. The spoilers only operate on landing or a rejected takeoff. Pilots could select reverse thrust (idle thrust only) on the inboard engines, #s 2 & 3, if they needed a steeper descent. They avoided this as the reversers often deployed a second or two apart causing an uncomfortable yawing motion.

[@user-po7xi9uw3j]

Hands down best channel.

[@pilot_obet7815]

Thank you sir- doing my best to share knowledge 😀

[@lorddunkie]

Another Brilliant Video Sir!

[@pilot_obet7815]

Thanks

[@TH33QUALIZ3R]

Captain, is that a 747-400? Your autobrake knob is in a different location compared to what I've seen in the 747-800 in Microsoft Flight Simulator. And are the thrust reversers "always" used upon landing the 747 or are there occasions when they don't need to be deployed at all. Thank you Captain, keep these educational videos coming. I learn more from your videos than I do from any other source if I'm honest.

[@jedus007]

Excellent video, that was highly educational 👌👌

[@pilot_obet7815]

Cheers

[@tonymax6632]

@pilot_obet. Excellent video. Again your mastery of teaching comes to the fore. Thank you. One question for you though sir. As with the C130 and C17, is it possible to reverse taxi this aeroplane??? I know you would not have a loadie peeking out of a half open ramp door to help guide you; it would be up to ground marshalling. Maybe it is somehow disabled as a safety item.

[@tsankara2705]

Thank you captain always looking forward to your videos now am ready to go to flight school 🇿🇼

[@pilot_obet7815]

Good- thank you 😊

[@annapaolagrandini1052]

You are right Captain: we are not bored and yes we are an aviation enthusiast 😄

[@priyeshpv]

Thanks a lot, very interesting video again! :-)

[@FeCadacio]

Hi Pilot Obet, God bless 🙏

[@daveterpening6801]

Another amazing video, thanks. Question: In a "typical" landing...what percentage of the overall stopping power comes from reverse thrust versus the brakes?

[@pilot_obet7815]

Aircraft senses deceleration rate based on combined brakes and revers thrust. If you land and don’t use reverse thrust, all the deceleration requirements are demanded from the brakes. With the same auto rake setting, if you use reverse thrust, the aircraft reduces the brake pressure to achieve the same total overall deceleration😊

[@marvinspates924]

Hi thank you for another awesome video! I did not have the opportunity to learn how to fly when I was younger! But now that I am older I enjoy being a flight simmer. I am enjoying flying at home. Your videos have cleared up a lot of questions that I have had about flying the 747!!! VR (Virtual reality) has really made flying as real as can be!! Do you fly GA aircraft in your spare time? If yes what type??? Thank!!!

[@pilot_obet7815]

I want to do some GA but time- location is not easy

[@markcardwell]

Isn’t there a thrust mode for reverse like the other phases of flight like TO, CL, etc.? TO was displayed on EICAS before and after reverse was selected but no mode was displayed in reverse??.??

[@apuwdm2]

Fantastic video. I appreciate your uncanny skill to anticipate the viewer's query, that is naturally expected to occur after viewing information in your video, and answering it with an actual example. A request - is it possible to show the actual mechanism that magically moves the throttle levers and other controls of an airliner at a predetermined rate and throw. Is this an electric motor? And can you override the moving lever with your hand i.e. can you push and overpower the electric motor moving the lever? I understand it may not be easy for you to open the control stand and show us the internal mechanisms, although you did show us the brakes or the reverse thrust cascades. However, at the minimum, can you show us the technical diagrams in the aircraft's maintenance manuals showing the mechanism for automatically moving the various levers?

[@pilot_obet7815]

I’ll try but that is a difficult one. I’ve seen some stills of the mechanism and yes you can override the electric motor and we occasionally do this when we think it’s behaving sluggish😊

[@sunwahandamillali7488]

Is auto thrust on from rolling to touch down during normal operation ?

[@user-bz8lc2ku4u]

Is it true that on the 747, after touch down if the pilot increase throttle from idle, autobrake will disengage and the speedbrake also automatically retract? I read the CAL 605 at KaiTak incident report and it said that's what happened after touchdown. Pilot flying moved thrust lever forward instead of engaging reverse thrust , disabling the autobrake and retracting the speedbrake. Both the PF and PM did not notice it until they're almost out of runway.

[@robertarnold9125]

What is the average landing speed for a large passenger plane

[@markcardwell]

So in full reverse what is thrust limit? I didn't see anything on primary EICAS but %n1 was about 83. Where did that limit come from? Is that the max % allowable??

[@thomism1016]

Another awesome video as usual. Please, what are speedbreaks? ⭐️❤️💐🥂

[@pilot_obet7815]

They are the panels that lift up on the wing to create drag in flight thus reducing speed of the aircraft: Speedbrake

[@thomism1016]

@@pilot_obet7815 Thank you, Capt. I love that you are able to answer the questions of your subscribers ❤️⭐️🇬🇧👍🏾

[@Someone_igidk]

Hey do you happen to know narscent?

[@TheJunior1964]

Why do the A380 airplanes only have two reverse thrusts and the 747 airplanes have four?

[@Dirk-van-den-Berg]

Dear pilot, just stumbled upon this video. One thing I still don't get: is reverse thrust a function of just letting air in passively trough the hole that the sliding sleeves open, and 'bounce' against the closed blocker doors outside forward? Or does the air still get compressed by the forward part of the engine and then let out of the engine?

[@pilot_obet7815]

Bounces off and escapes via the cascade vanes

[@dariustanz3410]

Captain will the reversers open in flight of the pilot selects the reverse thrust levers manually?

[@pilot_obet7815]

The answer is in the video and the narrative

[@anthonyglee1710]

Nice video. Remember it’s “Thrust Reverses” not “Reverse Thrust”

[@user-dw8ud2hw5d]

In full auto-land can the thrust reversers deploy automatically or does it always need pilot to deployment?

[@ImperrfectStranger]

They alway needs pilot input. The pilots control the reverser power and which engines to go into reverse.

[@robertoblanco1581]

Captain, For a normal landing do you bring the thrust reverse just to idle or do you pull back them completely?

[@pilot_obet7815]

Depends on landing weight/runway conditions

[@ImperrfectStranger]

May depend on airport noise restrictions. If the airport has a curfew, you may be allowed to land a little earlier if you don't use full reverse.

[@atcatc4575]

What if you use speed brake in the air ?

[@pilot_obet7815]

It slows down the aircraft- hence the name

[@abangss]

Can speedbrakes lever be close when reverse still open?

[@pilot_obet7815]

Yes

[@Kenny-en7wb]

Have you ever had a reverser door sticking on you?

[@pilot_obet7815]

Yes on ground

[@sukottora]

I'm sure it's not possible in practice, but if you were to leave the reverse thrusters on, would the plane come to a standstill and then start accelerating backwards as if it was attached to a big rubber band?

[@pilot_obet7815]

Yes it would! I’ll show you in a snippet soon

[@ImperrfectStranger]

Reverse thrust on 747's at low speed is not allowed. The airflow into the engine may become unstable and cause compressor stall.... i.e. you may get loud bangs and violent shaking. During engine test runs (aircraft not moving), sudden wind shifts may also cause compressor stalls and shift the nose of the aircraft sideways violently. I've heard of stories where the nose has moved 6 feet (rapidly) when the ground crew has failed to reduce thrust (Usually erratic indications on your instruments give you a clue that the engine is about to stall).

[@KingdaToro]

Are the thrust levers interlocked with each other? In other words, while you're on the ground can you simultaneously increase forward thrust on one engine and engage reverse thrust on another engine? Or does increasing thrust above idle on any engine block the reversers on all of them, and vice versa?

[@pilot_obet7815]

Ill show you in a clip…but I ask why? Who flies like that

[@KingdaToro]

@@pilot_obet7815 I don't think anyone does, I was just wondering if it was possible.

[@pilot_obet7815]

@@KingdaToro to select reverse thrust, you must have the thrust lever at idle- all of them. Mechanically not possible

[@atcatc4575]

Captain I think your bracelet is long and may cause problem one day when you try to adjust throttles

[@pilot_obet7815]

Ha ha- I usually remove it and I am not normally having my hands like that all the time- it was mostly for explanation- I thought you were more interested in the video lessen….not the bracelet 🙃

[@sebinamuwanga]

Captain Obet, did the throttles go to idle because the A/T was engaged? And if not engaged, the PF has to retard them manually, right? Secondly, in instances where the speed brake is used during the descent may be to slow down or descend faster as instructed by ATC and by coincidence, the throttles are in the idle position, is it possible to select idle reverse or reverse thrust? The reason why I ask is because with the speed brake fully or partly deployed, and the throttles at idle, the aircraft might think it is on the ground!

[@ImperrfectStranger]

The thrust levers went to idle because the autopilot was in Autoland mode. It's not possible to engage the thrust levers in the air. The landing gear must be compressed (i.e. weight on wheels) for the reverser logic to be satisfied.

[@elenacolon3880]

captain, speed breaks are 123 how do one knows which number to set it up with

[@pilot_obet7815]

Automatic system selection

[@ImperrfectStranger]

Do you mean the Autobrakes? They are 1, 2, 3, 4 and MAX. Selection depends on runway length, aircraft weight, passenger comfort, etc.

[@AKjohndoe]

I did a bad thing in flight sim.. I used my reversers to back out of a parking spot... Shhhhhh

[@MrEurocup]

Lauda Air Flight 004

[@ImperrfectStranger]

The reverser electronics have been modified/updated many times since that.