V ref vs. V approach

[RubberNeck]

Got into a discussion the other day where one of my fellow pilots said I landed (touch down ) to fast. I normally use Vref +10 and carry that to just before touch down throttles closed on the runway, so i'm usually +5 on the R/W unless the situation requires more or less "short r/w or gusty conditions."
This fellow routinely will fly ref+0 and touch down Vref -5-10 ....what the consensus????

Thanks
RN

 

[bigsky]

I guess I would say that with bigger airplanes excess speed can be an issue. I am trying to remember but I think the number stated in the md-11 is it takes an additional 2000 feet of ry if you hold the airplane off the ground to bleed off an extra 10kts of airpseed. touching down 10 kts fast takes an additional 400-600 feet wet or dry.
that being said I can say it is not a great idea to carry more than you need but I am not a big fan of getting slow either. Planning on ref + 0 sounds like a problem should you encounter any type of shear.
I have never seen any plane or operation that didnt use a minimum of ref + 5 as approach speed.

 

[ultrarunner]

Unless wind conditions dictate, if you're flying Vref +10 and not going to idle until touchdown, you're using WAY more pavement than necessary. Are you even making the touchdown zone?

At 50', Vref, close 'em. Unless of course Vref adjustments are dictated due to wind conditions.

 

[Fokkerflyer]

What kind of airplane? Recommended approach speeds vary by aircraft, based on wing design. Stick to what the manufacturer recommends, including gust correction.

 

[Spooky 2]

Unless wind conditions dictate, if you're flying Vref +10 and not going to idle until touchdown, you're using WAY more pavement than necessary. Are you even making the touchdown zone?

At 50', Vref, close 'em. Unless of course Vref adjustments are dictated due to wind conditions.

I'm not so sure that closeing the throttles at 50' is the best procedure, especially if your at Vref. Mybe I read something into your post that did not mean but I believe that if you were at Vref+5 at 50' and simply closed the throttles, assumming a no wind condition you would run out of airspeed prior to touchdown. Case in point from aprevious post talked about the MD11. I believe the AT start a power reduction at 47' when doing a Autoland and the B767-300 does the same thing around 30' so you can a simple "close'em" at 50' might not work for all aircraft. As for the corporate guys in the GV' BB700' I'm clueless but probably already new that anyway.

 

[ultrarunner]

I'm not so sure that closeing the throttles at 50' is the best procedure, especially if your at Vref. Mybe I read something into your post that did not mean but I believe that if you were at Vref+5 at 50' and simply closed the throttles, assumming a no wind condition you would run out of airspeed prior to touchdown. Case in point from aprevious post talked about the MD11. I believe the AT start a power reduction at 47' when doing a Autoland and the B767-300 does the same thing around 30' so you can a simple "close'em" at 50' might not work for all aircraft. As for the corporate guys in the GV' BB700' I'm clueless but probably already new that anyway.

I'll have to dig out Part 25, but I believe IF you want to make your published landing distance numbers, if that's important, then I believe that is based on the aircraft arriving at 50' feet, at ref with thrust levers at idle. A brainiac will chime in for sure to correct me.

Turbojet aircraft are not meant to be flown under power at ref+10 to touchdown. Now, you can do it, it's all about how much pavement you have in front of you and how much you're willing to leave behind you.

But keep that in mind one nasty rainy night when you're landing on runway 6 in TEB and you're at ref +10 at touchdown and then close the power levers.

I agree however in that some planes tolerate this practice better than others. Falcon drivers and straight-wing Citation drivers don't sweat Vref +10 NEARLY as much as a Lear driver, since the former has Vref of say 110 kts vs 135 knots.

You start adding 10 knots to ref speeds that start at 135 or 140 you better have some serious pavement in front you.

 

[G100driver]

I was alway taught to cross the fence at ref+5(or more for gust factor) and touch down on ref. Anything more than ref and you might as well not use your landing distance charts.

Now I am not that good, so I always use the 1.67 factor. After all, if I run off the runway, it sounds better at the hearing. Now that 91K is coming into effect I will probably switch to that.

 

[Rabble]

Vref is, by definition, 1.3 VSO. Tell the Lear driver to look at the AOA gauge next time he's flying at Ref +0. It's WAY in the green. Plenty of kinetic energy left for flying.

If you want to be at Vref +10, fine. But don't add a few more knots for the wind, and a few more for the wife and kids, and a few more for grandma...

On speed, on centerline, in the touchdown zone. Every time.

 

[ackattacker]

Again some braniac will surely chime in but my understanding is that per certification requirements the landing distance will be met with ref -5 to +15 at at a threshold height of 30ft. Now I'm really no expert but I typically split the difference and aim for +5.

 

[ultrarunner]

Vref is, by definition, 1.3 VSO. Tell the Lear driver to look at the AOA gauge next time he's flying at Ref +0. It's WAY in the green. Plenty of kinetic energy left for flying.

I am a Lear driver. And that's why I don't arbitrarily start adding knots to computed ref.

As you said, plenty of energy to fly at ref, unless wind conditions dictate otherwise.