VIDEO of managing drag during Approach

[Highiron 21]

I don't want to hi-jack this thread so I'll keep it simple. I see the problem. The first 700's delivered had no winglets. The record as I stated from Westjet did not mention the timeline of deliveries between 600's and 700's just that a "mix" of 20 was ordered. Upon further digging though my info, I found a inconvenient typo. In a different reprint of the same statement the word "or" is inserted between the 20 ordered aircraft. It would appear WJ clearly decided on the 700. My original document is missing that very important "or" indicating 600's were part of the initial early order in 2001. Since early 700's as well as the 600's had no winglets they were near indiscernible from each other to the untrained eye; (back then these things were new. After time the differences are more clear). It would indicate that I was rolling the early 700's and 600's together and assuming from a glance they were one and the same when they were not. Later orders of 700's did include winglets and were therefore very distinguishable as 700's. I had thought that all WJ 700's had winglets, hence misleading myself to believe, all none winglet aircraft were 600's. In the last few years this is most definitely true, as all the early delivery 700's have been sold off, meaning, anything flying today in the WJ fleet without winglets is a 600 series. This only went to further reinforce my conviction. For the record as per Boeings record, the order of deliveries and operation of 737's was 200's followed by 700's no winglets, 700's with winglets, 600's no winglets, then more 700's with winglets, previous 700's without winglets being traded off, and as Jack had mentioned the 800's from Delta. I imagine Boeing will further supply more 800's in the future. The info as you have described by Wikipedia is correct in it's timeline. My convictions were based on a WJ document with a typo, and my lack of clearly identifying 600's from 700's 11 years ago. I'm glad that error has now been permanently cleared up on my part. Whew! No, I did not work for Canadian. At the current time I am not working around YYC. My carrier went defunct through gross mismanagement, I won't give details, and I had to find alternate employment quickly outside commercial aviation. I had a back injury that invalidated my medical that I was just able to get back in time for the 09 recession. I just had my last surgery this week and can now get back to flying. I have many contacts at Jazz, Air Canada and Westjet, that will be able to get me back into the left/right seat again in hopefully short order. For now I tutor commercial pilots who are seeking upgrade training or refresher courses as I was a former Class II flight instructor in past years and still have most of my training material, it also helps to keep me from losing my edge. Yes, I still do love the loud and smokey 200's. Unfortunately their days are numbered. No more Royal Airlines 727's or Ace courier: not after scraping the back end of one down 28. The gouge is still visible in the pavement! Thanks for challenging me and making me dig. I now have correct info on the WJ aircraft history, now back on to the original topic.

[Buzz313th 0]

But a wing holding 140kips would need a greater AOA than the same wing at the same speed holding 130kips. No?

Yes it would, but mass in relation to drag is more of a linear curve where airspeed to AOA is not as linear. Airflow velocity has a bigger impact on a given airfoil AOA for level flight than wing loading caused by mass on the same airfoil. Atleast thats how I understand it. JB

[michal 44]

probably because a smaller AOA means less Induced drag, which would give mass and inertia the upper hand.

Why smaller AOA? AOA will be probably very comparable in both models of 737. Actually since wings are the same and the wing in -800 must support the higher weight - if there is any trend here - its' AOA should be higher at the same speed.

[Chaos81 110]

Great video Jack. I suspect this will help out my approaches, as I'm extremely terrible about coming in way too fast. Thanks for sharing.

[Tone89 0]

Thanks for the video Jack, I was one of the posters who had been struggling with deceleration towards the approach phase so I'll definitely take on board what I've seen from your video. Many Thanks, Anthony Hammond

[Buzz313th 0]

Why smaller AOA? AOA will be probably very comparable in both models of 737. Actually since wings are the same and the wing in -800 must support the higher weight - if there is any trend here - its' AOA should be higher at the same speed.

That was in reference to Jack mentioning that the 800's were harder to slow INITIALLY. And I took that as, the 800's were harder to slow when the airspeed is high. My comment was pointing out that at higher airspeed (lower AOA) would have less Induced Drag. I was not comparing the 800 to the 700 in that comment. JB

[macpac22 0]

Beautifully controlled approach, over the years I've been trying to finesse my approaches and make descents and changes in speed more smooth. Id love to see more videos showing more approaches and procedures.

[3-2-1-Now 126]

But a wing holding 140kips would need a greater AOA than the same wing at the same speed holding 130kips. No?

Get your head around this: a light aircraft and a heavy aircraft of the same type will take the same distance to descend from the same altitude, only the heavier aircraft will get there first. To put another way: best glide speed increases with weight, but the glide ratio remains the same. If we fly our light aircraft and heavy aircraft at the same PITCH and speed, the heavier aircraft will have a higher angle of attack due to the heavier mass. It requires a greater forward velocity in order to generate the lift needed to hold up the additional mass. This additional velocity results in the heavier aircraft flying faster than the lighter aircraft, but with the same pitch attitude and angle of attack. It is the lift to drag ratio that dictates the best glide speed. We need to fly at a certain speed for a certain mass in order to attain a particular angle of attack that results in the most lift for the least drag. This is why the glide ratio is constant for both aircraft, with the heavier aircraft simply flying faster, and why it will land in the same spot as our lighter aircraft, but sooner in time. Consequently, for any flight regime, the heavier aircraft must fly faster in order to get the same performance as the lighter aircraft. The sticking point is that there is a fixed amount of thrust, so consequently the heavier aircraft will not perform as well as the lighter aircraft as the available (excess) thrust can't be increased. We can however make the lighter aircraft perform the same as the heavier aircraft by reducing the thrust (and this forms the basis of FLEX takeoff). Whilst mass, and thus inertia, means the heavier aircraft takes more to slow down, the lighter aircraft should actually be harder to slow down as the relative residual thrust at idle is higher per unit of mass of the light aircraft vs. the heavier aircraft. Thus, the lighter aircraft will be more prone to accelerating, and requires more drag than the heavier aircraft for a particular rate of deceleration. How well this is modeled in FS is unclear. Best regards,Robin.

[Jack_C 1]

Get your head around this: a light aircraft and a heavy aircraft of the same type will take the same distance to descend from the same altitude, only the heavier aircraft will get there first. To put another way: best glide speed increases with weight, but the glide ratio remains the same. Best regards,Robin.

Yes but we are not talking about GLIDING. this is just slowing down in level flight.

[3-2-1-Now 126]

Maybe, but it was to demonstrate an important point; that being the heavier aircraft has greater inertia, but the lighter aircraft has less induced drag and greater residual thrust at idle, requiring more drag in the earlier stages of the approach in order to keep the speed in check. Best regards,Robin.

[DVA7475 0]

Now I don't have a problem slowing down on the approach, but what is bugging me is when I touch down, my autobrakes don't seem to be working right. I can put MAX autobrake, arm my spoilers and add reverse coming in at the speeds based on the Aircraft Operations manual and it doesn't seem to want to slow down at all. It will almost go off the end of a 10,000' runway, and I'm definitely not floating halfway down it. I touch down towards the beginning usually about 130-140 knots indicated and it just refuses to slow down. Thanks for any help, Connor G.

[Jack_C 1]

Hey Connor. I THINK that is a calibration issue or something. Make sure they are set up in fsuipc. In early stages of testing i bugged that too but i found out it was a calibration thing. Trut me, the autobrakes work fantastic on this.

[DVA7475 0]

Ok, I will try that out and let you know if it fixes anything. Thanks, Connor

[DVA7475 0]

Ok, I calibrated my brakes on FSUIPC, I don't think I'm doing it right, but strangely the brakes worked for about a minute and then it suddenly stopped and now its back to its normal antics. Is there a correct way to calibrate it in FSUIPC that maybe I don't know of? Connor

[altstiff 71]

Always amazes me that the pros landing at CYYZ are kept up to 170/180Kts to the OM! No dragging your arse in there....