BeechTalk - BT

Username Protected · **Posted:** 05 Feb 2021, 22:57

Username Protected wrote:

Thread Drift Alert:

Can someone lookup the required take off distance for a 421C at 9000ft density alt?

If it won't make it at gross, what weight will it?

I'm in Crested Butte Colorado this week vacationing next to the airpark and can't help but be curious.

I did a trip to CB (used GUC) in the summer a couple years ago, great fun. Rather than required take off distance, you might want to look at single engine performance. Taking off early on a summer day, I chose my take-off weight to get some margin on a positive climb rate OEI.

Username Protected · **Posted:** 05 Feb 2021, 23:07

At high density altitude and temps you might exceed the the tire limits.

Your normal 95 to 100 KTS IAS rotation speed will be a lot higher true airspeed.
That higher true AS may exceed the tire limits.

Check the rating on your tires for speed and temperature.

Username Protected · **Posted:** 06 Feb 2021, 10:17

Username Protected wrote:

At high density altitude and temps you might exceed the the tire limits.

Your normal 95 to 100 KTS IAS rotation speed will be a lot higher true airspeed.
That higher true AS may exceed the tire limits.

Check the rating on your tires for speed and temperature.

I think you mean ground speed.

Username Protected · **Posted:** 06 Feb 2021, 10:35

Username Protected wrote:

Thread Drift Alert:

Can someone lookup the required take off distance for a 421C at 9000ft density alt?

If it won't make it at gross, what weight will it?

I'm in Crested Butte Colorado this week vacationing next to the airpark and can't help but be curious.

The 0CO2 airport is already at 9000 ft. The only time it will have a density altitude of 9000 ft is when it's below freezing.

In the summer, the density altitude of that airpark is regularly over 10,000 ft. Lower terrain is to the southeast but the wind is often from the northwest. The canyon is about 1.5 miles wide at the airport and gets narrower as you go farther north.

Runway length is almost never the problem. Almost all density altitude accidents come from not being able to outclimb the surrounding terrain.

Username Protected · **Posted:** 06 Feb 2021, 12:24

Username Protected wrote:

At high density altitude and temps you might exceed the the tire limits.

Your normal 95 to 100 KTS IAS rotation speed will be a lot higher true airspeed.
That higher true AS may exceed the tire limits.

Check the rating on your tires for speed and temperature.

I think you mean ground speed.

Username Protected · **Posted:** 06 Feb 2021, 13:21

Username Protected wrote:

Ha, yes when the rubber is still on the ground they are both the same thing?

True airspeed is not equal to ground speed if there is any wind.

Mike C.

Username Protected · **Posted:** 06 Feb 2021, 16:42

SLOPES 2 PER CENT TO SE, LAND UPHILL RWY 29, TAKEOFF DOWNHILL RWY 11.

You have relatively rapidly falling terrain off the end of 11 and GUC is 25 miles away.

The key here would be taking off light. You take off with 40 gallons of fuel on board and top off at GUC and you don't load it up with 8 people and bags. A 421 at 1500 lbs under gross is a spunky little plane.

Username Protected · **Posted:** 06 Feb 2021, 20:03

Username Protected wrote:

Ha, yes when the rubber is still on the ground they are both the same thing?

True airspeed is not equal to ground speed if there is any wind.

Mike C.

Username Protected · **Posted:** 22 Feb 2021, 22:27

Friend of mine is looking at a 421 for sale in Texas. I suggested Juan at DFW for the prebuy but they've done some work on it over the years.

Any other 421 gurus in the Southwest for a prebuy??

Thanks.