V ref vs. V approach

[DrProc]

Just remember, there are more accidents being fast and running off the end of the runway then there are getting too slow and landing short of the runway.

 

[deadstick]

scroll to 7/1/06, there's a nice chat about Vref...

APTAP

 

[ksu_aviator]

I got in an argument with an examiner about this very point. I let him win the argument, but I verified my answer shortly after the check ride and I was correct.

I checked in the AFM under the performance section. It referred me to a chapter that explained the landing procedure. I suggest that you read that section for your aircraft because it may have some variences.

For the Lear 20's 30's and 45 the AFM gives a specific hat, speed and throttle location. They list 50 feet (55 in the 45) on Vref and throttle levers biskly moved to idle. Landing is then accoplished with minimal float and maximum breaking (thrust reversers are not factored into the landing performance).

 

[Waldom]

Performance calculations are based on Vref and decreasing at a point 50' over the threshhold. I don't believe anything is mentioned regarding a power setting in F.A.R. 25.

 

[gunfyter]

This fellow routinely will fly ref+0 and touch down Vref -5-10 ....what the consensus????

Thanks
RN

I vote for ref -5-10. Has worked for 25 yrs for me.

 

[TXDA2000]

Try this in any Falcon on an EMPTY leg, with a LONG runway.

Cross the fence normally, roundout and flare till the wheels are at 1 ft. Hold the aircraft at this altitude as long as you dare.

In the 2000, I've never had the guts to go below 80 kts. Still, below 90 it is very solid. This is from a ref of around 110.

The 2000 definitely likes the 50 ft at ref, power to idle approach. I can't imagine the 900 being much different with the same wing and higher weights/speeds.

 

[MauleSkinner]

Performance calculations are based on Vref and decreasing at a point 50' over the threshhold. I don't believe anything is mentioned regarding a power setting in F.A.R. 25.

It's not in Part 25, but as KSU pointed out, the individual manufacturers use slightly differing techniques, usually published somewhere in the airplane manuals (not necessarily the AFM). They may include power, or power reduced to idle at a certain point.

I don't know about the Falcon 900's, but the Falcon 10's were final and touchdown at Vref, and IIRC, there was something about a descent rate (600fpm comes to mind) at touchdown...IOW, no "greasers"

Fly safe!

David

 

[Seadogrun]

It's not in Part 25, but as KSU pointed out, the individual manufacturers use slightly differing techniques, usually published somewhere in the airplane manuals (not necessarily the AFM). They may include power, or power reduced to idle at a certain point.

I don't know about the Falcon 900's, but the Falcon 10's were final and touchdown at Vref, and IIRC, there was something about a descent rate (600fpm comes to mind) at touchdown...IOW, no "greasers"

Fly safe!

David

A good point to make is that the way they do it for flight testing is not a realistic way to fly everyday. They do it that way to get the smallest landing runway required as possible at least partially for marketing reasons. The result in flight testing of aircraft is very firm/hard landings, but they stop in the shortest distance. My approach is to achieve safety first then pax comfort, but if I can get both I'll do it that way. I also wouldn't land on a runway that is at the minimum required. I like the 135 landing numbers which will allow you to land safely and smoothely.

 

[2EASYPilot]

Try this in any Falcon on an EMPTY leg, with a LONG runway.

Cross the fence normally, roundout and flare till the wheels are at 1 ft. Hold the aircraft at this altitude as long as you dare.

In the 2000, I've never had the guts to go below 80 kts. Still, below 90 it is very solid. This is from a ref of around 110.

The 2000 definitely likes the 50 ft at ref, power to idle approach. I can't imagine the 900 being much different with the same wing and higher weights/speeds.

You would not think it was different but it is...we fly both and the 2000 is like a cub compared to the 900EX.

 

[AV8OR]

On app, ref +5-10 dep on a/c, slowing to ref at the runway tdz, centerline. IMO

 

[Waldom]

It's not in Part 25, but as KSU pointed out, the individual manufacturers use slightly differing techniques, usually published somewhere in the airplane manuals (not necessarily the AFM).

I should know better than to pull an answer out of my memory bank. I don't have a copy of F.A.R. 25 to consult on my bookshelf. [I usually check references before a post in an attempt to keep my foot out of my mouth].

 

[CL600Pilot]

I got in an argument with an examiner about this very point. I let him win the argument, but I verified my answer shortly after the check ride and I was correct.

I checked in the AFM under the performance section. It referred me to a chapter that explained the landing procedure. I suggest that you read that section for your aircraft because it may have some variences.

For the Lear 20's 30's and 45 the AFM gives a specific hat, speed and throttle location. They list 50 feet (55 in the 45) on Vref and throttle levers biskly moved to idle. Landing is then accoplished with minimal float and maximum breaking (thrust reversers are not factored into the landing performance).

That's the same way Cessna does basically - the Cessna charts (at least in the Ultra and XLS) are predicated on crossing the threshold at 50' agl, at Vref, and throttles at idle. This of course means that you will be slower than Vref when you actually touchdown. The airplane doesn't fall out of the sky at Vref.......or even at Vref-10.

 

[DoubleB]

Throttles to idle at 50ft - WOW!!

For what it's worth, I'd be very careful of blindly advising anyone to "go to idle at 50 ft". I assure you that even at ref plus 10 there are some aircraft that will come out of the sky like a sack of SHIITE if you do that.

For my money, ref plus 10 on the approach, power reduction as appropriate to arrive on the runway at ref in the touchdown zone.

WHen you go to idle depends on 1) aircraft type (wing loading is a big factor), 2)weight and 3) wind conditions.

Go to idle in a 767 or a G200 at 50' and ref plus 10, and I assure you that the results will be very unpleasant.

 

[Raskal]

For what it's worth, I'd be very careful of blindly advising anyone to "go to idle at 50 ft". I assure you that even at ref plus 10 there are some aircraft that will come out of the sky like a sack of SHIITE if you do that.

For my money, ref plus 10 on the approach, power reduction as appropriate to arrive on the runway at ref in the touchdown zone.

WHen you go to idle depends on 1) aircraft type (wing loading is a big factor), 2)weight and 3) wind conditions.

Go to idle in a 767 or a G200 at 50' and ref plus 10, and I assure you that the results will be very unpleasant.

I have to agree with some of the above, I routinely cross the threshhold in the hawker 1000 at ref and end up touching down (closing the throttles at around 30ft) at ref -5 to -10 with no issues (in reasonable tolerable wind conditions), any more speed and the float is a bit much. However, try this in a hawker 700 and the results are quite often unpleasant for all aboard, that thing is a brick.

I haven't flown the falcons, but I'd have to think it's based on individual aircraft characteristics (regardless what part 25 says). As safe and smooth as possible, with safety being primary is the goal. If your technique works, it works-but as I learned quickly, adjust it for the aircraft-not a general rule.

 

[BenderGonzales]

I believe that the original poster was addressing those pilots who bug Vref and Vapp, then fly Vapp plus additives.

If you are flying Vapp plus a gust factor, plus a few knots for grandma and the kids... you are crossing the fence at Vref +20 or so. That's a lot of kinetic energy to rid yourself of in the flare, and the dissipate with brakes before the end of the runway.

My operator requires a stabilized approach in VFR conditions by 500 AGL. Vref plus 1/2 the gust factor, configured, and engines spooled. If those conditions aren't met, a missed approach is required.