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### How to calculate Vx for a propeller driven airplane? [duplicate]

I know that Vx for jet engines airplane is at Vmd and that Vy is at 1.32 Vmd; I do also know that Vy for propeller airplanes is at Vmd. Now I cannot figure out where i can get the Vx for propellers.
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### How can best glide speed be lower than best rate of climb speed?

I was looking up V-speeds for C172. I don't have easy access to an official copy of the POH, but online I found: $V_y$, best rate of climb speed (at sea level): 76 KIAS (p22) $V_{glide}$, maximum ...
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### What is the relation between aircraft descent rate and speed?

I am an ATCO working in India. I am trying to understand why an aircraft's rate of descent increases, when its speed increases. I am particularly interested in how it relates to jet engine aircraft. ...
• 211
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### What is the typical climb angle (versus the ground) of a single engine piston plane?

What are the normal climbing angles against ground on a SEP (single engine piston) plane and an airliner? (no wing-air angles in here, but the climb angle when watched from the side of the plane) (...
1k views

### Why do Vx and Vy coalesce at an airplane's absolute ceiling?

I'm struggling to figure out why that is the case. I'm trying to determine why the best angle of climb speed equals to best rate of climb speed at the absolute ceiling on airplanes.
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### How does climb-rate vary with density/pressure altitude?

I'm seeking to write a little web or phone app which can help me choose the best cruising altitude based upon winds aloft. I know Garmin Pilot (and probably Foreflight) have a cruising altitude ...
• 309
2k views

### How does setting takeoff flaps improve aircraft performance?

A study guide I recently found indicates that Vmc and aircraft performance improve with takeoff flaps set. The Vmc improvement makes sense but the performance improvement does not. At a basic level, ...
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### Does the flap settings for the best lift/drag ratio change with speed on the Diamond DA20-A?

As I've recently started time building in DA20, I've noticed the AFM suggests flaps at T/O for a glide. Being very intrigued by this I run across this post. Although I appreciate Peter's reply that ...
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### For a flying wing airfoil, which AOA is to consider when selecting Cl?

I'm in the process of designing a flying wing. I'm trying to keep it a small as possible, so the lift coefficient is very crucial for me. I'm currently looking at some airfoils but most of them ...
• 241
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### How to calculate optimal flight climb angle?

I am trying to calculate the optimal flight climb angle based off of some basic power calculations for an aircraft on steady climb with an angle of theta. Doing a balance of forces I obtained the ...
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759 views

### How to calculate the best climb rate and glide rate?

Considering the lift equation $$L = C_L \frac{1}{2}\rho v^2 s$$ Given $P$ is 1,000 ft, $\rho$ is 0.002308, and $V$ is the cruise speed of a Piper Archer or 126 knots, we get L = (0.4) (0.002308) (...
257 views

### What would the effect be of flap deployment on a UAV such as the Reaper or Predator?

I've read answers that said that the climb performance is usually worse with flaps extended, and the pilots would, if they could, just retract them and get into a clean config as soon as possible. ...
1 vote
318 views

### Determine Vx and Vy from other climbing rate datas

I am developing a small program, working with Microsoft Flight Simulator 2020. For now, I can show my takeoff graph which display the altitude on the y axis and the distance in x axis. I would like to ...