Simple F-16 landing question. (Sorry if this has already been done to death)

[SickSidewinder9]

When setting up for final, what altitude AGL (from the runway's height, obviously) and what distance (at least in slant range, if not straight line, too) do I want to aim for?

(Not doing a break landing)

Edited June 10, 2022 by SickSidewinder9

[razo+r]

Usually, you get like per 3 miles ~1000 feet, and final is also around 8 miles max, give or take a bit. But of course you can also do visual approaches or approaches with a short(er) final. But I'd say per 3 miles 1000 feet AAL (Above aerodome level) is a good rule of thumb for a 3 degrees approach.

[Aquorys]

An advantage of modern jets like the Viper is that they don't just show you your airspeed and vertical speed, they also show you the flight path in degrees, so you can just use basic trigonometry to calculate any one of distance/altitude/glide angle from the other two.

As it has already been mentioned, a typical final of 3 nm equates to 955 ft above ground, obviously 6 nm is twice that. If you want to descend quickly, you get about 1:1 distance in nm to altitude in 1000 ft it you keep descending at an approximately 9 degrees angle (meaning you'll descend ~15k ft in 15 nm).

The formulas you are looking for are:

g = arctan(a / (6076 * d))
d = a / (6076 * tan(g))
a = tan(g) * d * 6076

where g is the glide angle, d is the distance in nautical miles and a is the altitude in feet.

Note that different calculators use different inputs for trigonometric functions, so you might need to convert (e.g., mine expects radians, not degrees).

[pierscockey]

Quick rule of thumb is 1/3 of your altitude. 

So at 9nm, you want to be at 3k ft

4.5nm would be 1.5k ft  

1nm 330ft.

That gives you your 3 degree rate of decent.   

 

 

Edited July 5, 2022 by pierscockey

[Frederf]

Put the threshold between the 2.5 dashes on the HUD. Put the FPM on the first inch of tarmac until you get to transition height.

[SickSidewinder9]

Thanks.
Working on my landings.  I was bouncing a bit.  Now after watching some videos on straight in landings and break landings, I'm running over the runway.
Just more practice I guess.  I am aware of all the symbology I need to line up.  I think it's my touchdowns and rollouts that are my problem.  The HUD symbology actually makes it super easy to touch down right where I should, even at a decent alpha.

[Frederf]

Aim nice and early on the approach. The roundout will take you plenty far down the runway so feel free to approach even a few feet in the dirt before the runway. Make the transition very slowly over several seconds. It's not a hard or fast input on the stick. Throttle usually significantly comes back about 2/3rds through the roundout. I like to put the top of the circle part of the FPM symbol tangent with the horizon line on touchdown. Shoot for contact at 13 AOA. Even with small vertical rate on touchdown it will feel like a bounce. The gear is hard and narrow.

Post touchdown aim for 13 AOA for aerobraking, light up the green donut symbol on the AOA indexer. By 100 knots or a bit more you can put the nose down, apply brakes, open speed brakes, and hold back on the stick.

[Fuggzy]

On 6/11/2022 at 3:11 PM, SickSidewinder9 said:

Thanks.
Working on my landings.  I was bouncing a bit.  Now after watching some videos on straight in landings and break landings, I'm running over the runway.

I've noticed that air-braking on the rollout seems to work very well. Pulling speed brakes and keeping the nose pitched up 5 degrees after touchdown gets her quickly down to 100kt and then wheel brakes become effective. 

late edit: not 5 degrees, definitely more like 10

Edited June 19, 2022 by Fuggzy

[Xavven]

Touchdown on the rear gear and hold the nose at something like 11°-12° until 100 kts, and do not hold the speedbrakes switch aft during the aerobrake. They are automatically retracted slightly from max to avoid hitting the runway, but the pilot holding the speedbrake switch forces them to max, increasing the chance of a strike.

Then allow the nose to drop and pull aft fully before the nose touches the ground so it touches gently. 

Then hold your speedbrakes switch aft fully to further extend the speedbrakes to max and begin applying wheel brake. If I'm not mistaken, you want to switch to full forward stick Think I got that wrong, it's full aft stick to increase down-pressure on the rear wheels which increases traction and improves braking performance and handling.

Engage nosewheel steering at what, 60 kts I think?

Edited June 19, 2022 by Xavven

[RuskyV]

This is a great video, clear and concise with no over complications.

 

[DD_fruitbat]

On 6/10/2022 at 9:03 PM, SickSidewinder9 said:

When setting up for final, what altitude AGL (from the runway's height, obviously) and what distance (at least in slant range, if not straight line, too) do I want to aim for?

(Not doing a break landing)

 

 

Why would you want to do a non break landing if you're doing a visual approach? Only time I ever come straight in is on an instrument approach.

Besides, break landings are much more fun,

 

Edited June 19, 2022 by DD_fruitbat

[Ignition]

On 6/10/2022 at 5:03 PM, SickSidewinder9 said:

When setting up for final, what altitude AGL (from the runway's height, obviously) and what distance (at least in slant range, if not straight line, too) do I want to aim for?

(Not doing a break landing)

 

Downwind is at 1000ft AGL 1nm from the runway (I do 1.2-1.5 if I have more weight), when the wing is aligned with the end of the runway start your base turn and I do about -3 degress pitch down. On final extend the air breakes and put the dashed horizontal line (-3º glide slope) on the end of the runway.

You know the rest.

Breake landings are for formations, this way they are easy to control and faster to land when multiple aircrafts arrive to the airport.

[Frederf]

Overhead is 1500' until perch. Speed brake should be out since break turn. Lateral spacing is visual about at missile rail. Key position is where threshold shows up behind wing edge. Base turn is quite steep. Roll out on glide path about 300' AGL.

[Fuggzy]

10 hours ago, DD_fruitbat said:

 

Why would you want to do a non break landing if you're doing a visual approach? Only time I ever come straight in is on an instrument approach.

Besides, break landings are much more fun,

 

lol that video is how I land 90% of the time, only because this is a simulator and I won't die

Edited June 19, 2022 by Fuggzy

[SickSidewinder9]

Getting a lot better.  But I'm still curious what the optimum altitude above the airfield I should be at 10 miles.  I haven't quite gotten it.

[Frederf]

Ten miles is 60,760'. Normally you'd be on a 2.5° or 3.0° glideslope. That's 2652' and 3184' respectively. You always want to intercept from below and close enough to see the PAPI and not take forever on final.

Typical is something like 2000' level at 10nm, 1500' is fine too for a closer intercept but they try to avoid that because that's overhead height. If you had at least 15nm and were committed to 3.0° then 2500' would be fine. Anything much higher is rare. Look around at approach charts for civil airports; they're around 2000.

ORD ILS 04R 1500' at 4.4sm

SMF ILS 17L 1875' at 5.7sm

Those are ILS so on the higher end for distance, height, and steepness. Visuals can be comfortably inside these values.

 

 

[SickSidewinder9]

Ok, so stay at 2000' above airfield, got it.  That dashed line when wheels are down is 2.5 degrees, right?

[Frederf]

Yup, it's smack between the horizon line and the -5 line.

[jojyrocks]

Maintaining the aerobrake angle, after landing, has become much more difficult after the recent patch.

[Lace]

On 6/19/2022 at 12:57 PM, DD_fruitbat said:

 

Why would you want to do a non break landing if you're doing a visual approach? Only time I ever come straight in is on an instrument approach.

Besides, break landings are much more fun,

 

 

Why did you land downwind?  I mean, apart from everything else that was wrong with that approach... 

 

[DD_fruitbat]

On 6/27/2022 at 5:57 PM, Lace said:

Why did you land downwind?  I mean, apart from everything else that was wrong with that approach... 

 

Because I can, and I'm fully aware of what the wind is in that mission, and its negligible, (it might of even been off then, cause we turned it off for a bit because of a bug with warbirds for a while on the beta).

Mainly because I can though. 

 

[darkman222]

The F16 has been updated so often. There are so many different youtube tutorials around now.

When I start the base leg to final approach at 1500 ft AGL and 220 kts. What comes next? What AOA and how many degrees nose down do I fly now?!

[Frederf]

There is no super exact procedure. You want to be on the same page as your squadron because your 5 sec break won't mean a 10 sec touchdown interval if you are too different.

By the -1 book you want to have 13 AOA throughout the base turn. The geometry of lateral sep, key visual position, and 300' roll out target dictates a certain radius turn. That means a certain speed/g combo. That means a certain throttle position. The -1 has a formula for the airspeed going through base varying with GW.

For me I put in healthy bank, set throttle mid way, fill the HUD 4/5ths with dirt, and pull for green doughnut AOA. A common occurrence is not pitching steep enough which makes the radius big because you're unable to pull harder without exceeding 13 AOA. Then you roll out way wide and high. If you don't roll out about 300' on that 2.5° path there is a fix.