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LRW

Takeoff Ref - V1 = Vr

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I was just watching the JustPlanes Air Canada 777-200LR CYYZ-CYVR-YSSY DVD and in the first leg (starting around 8:30 in the video) they are setting the takeoff speeds.  The EFB shows V1=154, Vr=154, V2=156.  They enter Vr as 155 in the CDU and FO Steve T. says "We'll change our Vr to a different speed; it can't think in the same speeds".

 

Can anyone explain that?  And is it the same in the 777 and 737?  I don't recall having any issues if the speeds were the same in the NG.  Somewhere in the past 18 months I picked up the habit of changing them if they were the same but I don't remember why.  I couldn't find any mention of it in the 737 FCOM v2 or FCTM.

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I'm not sure how it works, but the 777 and the 737 are two different planes, so even if they are made by the same company there's no guarantee that they will work the same way.

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Can anyone explain that?

 

Remember that the speeds are meant for different purposes:

V1 is a takeoff rejection speed

Vr is rotation speed

V2 is takeoff safety / engine out speed

 

While they're often sequential, given the right conditions they may well be the same.  This isn't an "issue," really, it's just speeds that happen to be the same.  The captain was just showing his own quirk by not liking that they were the same, which is a similar sentiment as to why it seems odd enough to you to raise the question here.

 

The J41 V1 speeds are also Vr.  When I fly small aircraft, I don't really think about V1 because V1 is well beyond where I'd hit Vr (that and if I lose an engine, there really isn't an option for a V2 climbout - haha).

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I also have a question for this DVD, in the end when they are at the gate at Sydney, I think I heard someone say we'll leave the seatbelts on for spray down, if IIRC what does this mean?

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I also have a question for this DVD, in the end when they are at the gate at Sydney, I think I heard someone say we'll leave the seatbelts on for spray down, if IIRC what does this mean?

Might be pesticides, Australia is extremely defensive of any foreign plants entering the country via flights.

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I believe he meant for the auto callouts of v1 and rotate by the aircraft. If both speeds are the same it can't call out both.

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I also have a question for this DVD, in the end when they are at the gate at Sydney, I think I heard someone say we'll leave the seatbelts on for spray down, if IIRC what does this mean?

 

When you arrive in Australia (from overseas) customs normally come into the aircraft and use spray bottles to remove any insects to prevent the spread of parasites which carry diseases dangerous to humans, such as Malaria and Dengue Fever.

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It depends upon the operating procedures of the airline.

 

We let the aircraft calculate the Vr and V2 speeds (the aircraft will not calculate v1) when the performance loading is complete then cross check it against a computer generated performance printout from the ACARS. The aircraft generated speeds must be within 3 knots of those provided by the performance computer over ACARS. If not then either the ACARS data sent to the performance computer was wrong or the weights entered into the FMC during the critical data setting procedure were wrong.

 

This enables a cross checking of the take off data to be performed for safety.

 

The performance figures generated by the computer over ACARS are always entered over the FMC generated figures. The MACTOW is entered and the trim setting checked against the stab green band.

 

If the speeds for Vr and V2 are the same then you only need to confirm the FMC data by pressing the relevant LSK.

 

V1 and Vr are often co-incident, the aircraft will call V1 and the non handling pilot will call rotate. On our aircraft there is no auto callout that I have ever heard for Vr. ( I don't know if it is there but disabled as there are a multitude of airline specific options on the 777 systems.)

 

Hope that helps.

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When you arrive in Australia (from overseas) customs normally come into the aircraft and use spray bottles to remove any insects to prevent the spread of parasites which carry diseases dangerous to humans, such as Malaria and Dengue Fever.

 

I find it kinda funny that a country that has so many deadly species of animals roaming around is so worried about deadly parasites...

Well! We spared you from malaria, but good luck afterwards.  If it's not the funnel web spider, or the taipan, or the box jelly, or the brown snake, or any of the others on that long list, you may still get a roundhouse kick to the face by a kangaroo.  Good luck, mate!

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New Zealand does the spray too. Saw it on a around the world video for a Lufthansa MD11. They explain it pretty good on there. I think it should be done on any aircraft coming into and from another country. The speed germs can spread in this day and age of flight is scary.

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V1 and Vr are often co-incident, the aircraft will call V1 and the non handling pilot will call rotate. On our aircraft there is no auto callout that I have ever heard for Vr. ( I don't know if it is there but disabled as there are a multitude of airline specific options on the 777 systems.)

 

Yes, that how it was done on the Air Canada videos I've seen, the auto callout for V1 and the PNF calling "rotate".  Thanks for the explanation.

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I find it kinda funny that a country that has so many deadly species of animals roaming around is so worried about deadly parasites...

Well! We spared you from malaria, but good luck afterwards.  If it's not the funnel web spider, or the taipan, or the box jelly, or the brown snake, or any of the others on that long list, you may still get a roundhouse kick to the face by a kangaroo.  Good luck, mate!

 

It's not just human diseases, but also parasites and diseases that might affect agriculture (crops and the like). It's for the same reason that the US confiscates your foodstuffs if you fly in from abroad.

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It's for the same reason that the US confiscates your foodstuffs if you fly in from abroad.

 

It certainly makes sense - don't get me wrong.  I just found it funny.

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Numerous aircraft end up usually having the same V1 and Vr speed. (The J41 for instance always has the same V1 and Vr) It's mostly a function of the runway length you have available and the power the aircraft has. 777's are so overpowered that you need a pretty short runway before you start getting V1 and Vr to differ significantly. You can read them being the same as "It's safe to reject the takeoff all the way up to rotation speed." With a shorter runway or less power you'd be committed to flying much earlier in the roll.

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Numerous aircraft end up usually having the same V1 and Vr speed. (The J41 for instance always has the same V1 and Vr) It's mostly a function of the runway length you have available and the power the aircraft has. 777's are so overpowered that you need a pretty short runway before you start getting V1 and Vr to differ significantly. You can read them being the same as "It's safe to reject the takeoff all the way up to rotation speed." With a shorter runway or less power you'd be committed to flying much earlier in the roll.

The question is though, why did the pilot in the video override the Vr setting so that V1 would not be the same as Vr, even though according to the performance calculations they should be the same?

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The question is though, why did the pilot in the video override the Vr setting so that V1 would not be the same as Vr, even though according to the performance calculations they should be the same?

OCD i'm guessing lol. I can't think of any good reason.

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The question is though, why did the pilot in the video override the Vr setting so that V1 would not be the same as Vr, even though according to the performance calculations they should be the same?

I decided to check this out with my father, he mentioned that when he initially moved to the 777 the topic of balanced field v speeds was brought up however he's been on the 777 for a while now and nothing further has ever been mentioned and no requirement has been made to increase VR. He also mentioned something about a possible software update for EFB calculated v speeds.

 

How old is that Air Canada video? I'm with the answer that it is something to do with the auto V1 call out on some machines conflicting with the PNF calling rotate at the same time, on other types if the v speeds are balanced you don't call V1, you just say rotate.

 

Bottom line 1knot is not really something to get deep about. Every operator has its own way of doing things.

 

EDIT- btw, for anyone interested, do some research for 'improved climb' on the 777, it is a method of increasing VR to obtain better climb perfomance.

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How old is that Air Canada video?

 

That flight of ACA033  was 16 July 2010.

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My guess is that maybe it was going to aurally announce "vee one" and "rotate" right at the same instant and possibly they do that to stop the callouts from overlapping.

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By googling the 777FHB and opening the corresponding pdf (not linking here as they are property of the company) it seems there is a difference between V1 and Vr for flaps 5.

 

Weight, V1, Vr, V2

170, 111, 122, 135 

230, 139, 146, 155

300, 163, 170, 175

 

Not sure though if such difference is enough to avoid overlapping V1 and Vr though, as I have no clue on acceleration of B777 :)

 

Aleks

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Field performance and climbout performance will affect the V1/Vr split the most on the 777.

 

Wet figures in particular will often give you a split. Also terrain constraints in the climbout and intersection departures will often give you a split on performance limiting runways such as Denver. The V speeds can be affected by using 'packs off' take off, 'improved climb' or 'full power' (selecting packs off takeoff will always give you a full power takeoff) to increase the TOPL (Take Off Performance Limit) to allow greater aircraft commercial loading from such performance limiting fields (Denver, Nairobi, Jo'Burg and Mexico City spring to mind!)

 

The FMC will calculate the V figures based upon your weight, outside air temperature, flap setting and trim. These are overwritten by the EFB (if fitted) or computer generated figures. In our company it is forbidden to manually adjust the figures unless calculated from the performance manual for manually calculated V figures.

 

I've been on the 777 for quite a while now and never heard of manually splitting the V figures to be able to call both the V1 and the Vr, neither would I, personally, allow it. Perhaps it is just either the Air Canada SOP or a personal foible of the Captain on the day.

 

(edited to add the correct term TOPL)

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I've flown various aircraft over the years at several different airline (including RRs old airline)... On many aircraft V1 and VR can be the same... on the A319/20/21 sometimes V2 was less then VR.

I dont really post much on here, Im more a lurker.. Having flown 2 of the PMDG aircraft (J41, 744) I have to say these products are amazing... I was never much into FS until someone introcduced me to PMDG and I was shocked at how real they model the aircraft... the NGX is unreal. I cant wait to see the 777... I havent checked on the status in a few months... I was just actually sitting down thinking I was gonna buy it... ha ha ha to my suprise no 777 cant wait to see this beast! Paul M

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Gents-

 

Since the above poster had a BlueRidge callsign, he can be trusted.  B)

 

Best little airline ever to run itself into the ground, right Paul?

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Rob I couldn't have said it any better myself. I actually just stayed at the IAD Holiday Inn over by Shaw Rd. I took a walk through the parking lot and around the old building, I'm man enough to say I got a bit teared up.

The 777 looks amazing... I'm now checking the PMDG website and here everyday! You've got another one hooked!

 

Paul

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I actually just stayed at the IAD Holiday Inn over by Shaw Rd. I took a walk through the parking lot and around the old building, I'm man enough to say I got a bit teared up.

 

Did it still have the Independence Air sign on it?  That thing was up for years after we closed up shop.  Despite living only a few minutes away, I haven't been back over by the old building in a while.

 

Oddly enough, I let my friend borrow my wands and part of my old rampie uniform for Halloween last year and just picked it up from her today.  The bag I gave her still has the RF100s, some unopened ear plugs and a commemorative RJ pin of some sort.  Crazy...

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