The recent and upcoming fly ins pose some interesting terrain/elevation issues. Here's a quick and simple refresher on how to quickly determine a minimum safe altitude to get to your destination.
http://download.aopa.org/epilot/2006/tap.pdf
Flying to an Event? Terrain Avoidance?
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
Flying to an Event? Terrain Avoidance?
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
And, excerpt from AC 61-134
( http://download.aopa.org/epilot/2006/ac61-134.pdf )
7-5-5. MOUNTAIN FLYING. a. Your first experience of flying over mountainous terrain (particularly if most of your flight time has been over the flatlands of the Midwest) could be a never-to-be-forgotten nightmare if proper planning is not done and if you are not aware of the potential hazards awaiting. Those familiar section lines are not present in the mountains; those flat, level fields for forced landings are practically nonexistent; abrupt changes in wind direction and velocity occur; severe updrafts and downdrafts are common, particularly near or above abrupt changes of terrain such as cliffs or rugged areas; even the clouds look different and can build up with startling rapidity. Mountain flying need not be hazardous if you follow the recommendations below. [AC Comment: As in all types of new flying, you should find a qualified and currently certificated flight instructor for a local area checkout.]
b. File a flight plan. Plan your route to avoid topography which would prevent a safe forced landing. The route should be over populated areas and well-known mountain passes. Sufficient altitude should be maintained to permit gliding to a safe landing in the event of engine failure.
c. Don't fly a light aircraft when the winds aloft, at your proposed altitude, exceed 35 miles per hour. Expect the winds to be of much greater velocity over mountain passes than reported a few miles from them. Approach mountain passes with as much altitude as possible. Downdrafts of from 1,500 to 2,000 feet per minute are not uncommon on the leeward side.
d. Don't fly near or above abrupt changes in terrain. Severe turbulence can be expected, especially in high wind conditions.
e. Some canyons run into a dead end. Don't fly so far up a canyon that you get trapped. ALWAYS BE ABLE TO MAKE A 180 DEGREE TURN! f. VFR flight operations may be conducted at night in mountainous terrain with the application of sound judgment and common sense. Proper pre-flight planning, giving ample consideration to winds and weather, knowledge of the terrain and pilot experience in mountain flying are prerequisites for safety of flight. Continuous visual contact with the surface and obstructions is a major concern and flight operations under an overcast or in the vicinity of clouds should be approached with extreme caution. g.
When landing at a high altitude field, the same indicated airspeed should be used as at low elevation fields. Remember: that due to the less dense air at altitude, this same indicated airspeed actually results in higher true airspeed, a faster landing speed, and more important, a longer landing distance. During gusty wind conditions which often prevail at high altitude fields, a power approach and power landing is recommended. Additionally, due to the faster groundspeed, your takeoff distance will increase considerably over that required at low altitudes. h. Effects of Density Altitude. Performance figures in the aircraft owner's handbook for length of takeoff run, horsepower, rate of climb, etc., are generally based on standard atmosphere conditions (59 degrees Fahrenheit (15 degrees Celsius), pressure 29.92 inches of mercury) at sea level. However, inexperienced pilots, as well as experienced pilots, may run into trouble when they encounter an altogether different set of conditions. This is particularly true in hot weather and at higher elevations.
And, from personal experience, consider circling over a departure airport to gain altitude rather than heading off into rising terrain. Once that terrain is filling the windshield, it may be difficult (and distressing) to turn around, especially if on the lee side of local winds. ("Come on, baby...don't sink...come on...")
Ice, even in summertime, can easily be found in precip/clouds in mountainous areas. Even a light frosting of the wings/propeller will turn an arduous climb into a nimble, nose-up, behind-the-power-curve descent ... with nowhere to descend.
Just hoping to get folks to thinking about keeping the summer trip a pleasant one.
( http://download.aopa.org/epilot/2006/ac61-134.pdf )
7-5-5. MOUNTAIN FLYING. a. Your first experience of flying over mountainous terrain (particularly if most of your flight time has been over the flatlands of the Midwest) could be a never-to-be-forgotten nightmare if proper planning is not done and if you are not aware of the potential hazards awaiting. Those familiar section lines are not present in the mountains; those flat, level fields for forced landings are practically nonexistent; abrupt changes in wind direction and velocity occur; severe updrafts and downdrafts are common, particularly near or above abrupt changes of terrain such as cliffs or rugged areas; even the clouds look different and can build up with startling rapidity. Mountain flying need not be hazardous if you follow the recommendations below. [AC Comment: As in all types of new flying, you should find a qualified and currently certificated flight instructor for a local area checkout.]
b. File a flight plan. Plan your route to avoid topography which would prevent a safe forced landing. The route should be over populated areas and well-known mountain passes. Sufficient altitude should be maintained to permit gliding to a safe landing in the event of engine failure.
c. Don't fly a light aircraft when the winds aloft, at your proposed altitude, exceed 35 miles per hour. Expect the winds to be of much greater velocity over mountain passes than reported a few miles from them. Approach mountain passes with as much altitude as possible. Downdrafts of from 1,500 to 2,000 feet per minute are not uncommon on the leeward side.
d. Don't fly near or above abrupt changes in terrain. Severe turbulence can be expected, especially in high wind conditions.
e. Some canyons run into a dead end. Don't fly so far up a canyon that you get trapped. ALWAYS BE ABLE TO MAKE A 180 DEGREE TURN! f. VFR flight operations may be conducted at night in mountainous terrain with the application of sound judgment and common sense. Proper pre-flight planning, giving ample consideration to winds and weather, knowledge of the terrain and pilot experience in mountain flying are prerequisites for safety of flight. Continuous visual contact with the surface and obstructions is a major concern and flight operations under an overcast or in the vicinity of clouds should be approached with extreme caution. g.
When landing at a high altitude field, the same indicated airspeed should be used as at low elevation fields. Remember: that due to the less dense air at altitude, this same indicated airspeed actually results in higher true airspeed, a faster landing speed, and more important, a longer landing distance. During gusty wind conditions which often prevail at high altitude fields, a power approach and power landing is recommended. Additionally, due to the faster groundspeed, your takeoff distance will increase considerably over that required at low altitudes. h. Effects of Density Altitude. Performance figures in the aircraft owner's handbook for length of takeoff run, horsepower, rate of climb, etc., are generally based on standard atmosphere conditions (59 degrees Fahrenheit (15 degrees Celsius), pressure 29.92 inches of mercury) at sea level. However, inexperienced pilots, as well as experienced pilots, may run into trouble when they encounter an altogether different set of conditions. This is particularly true in hot weather and at higher elevations.
And, from personal experience, consider circling over a departure airport to gain altitude rather than heading off into rising terrain. Once that terrain is filling the windshield, it may be difficult (and distressing) to turn around, especially if on the lee side of local winds. ("Come on, baby...don't sink...come on...")
Ice, even in summertime, can easily be found in precip/clouds in mountainous areas. Even a light frosting of the wings/propeller will turn an arduous climb into a nimble, nose-up, behind-the-power-curve descent ... with nowhere to descend.
Just hoping to get folks to thinking about keeping the summer trip a pleasant one.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
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briancbaker
- Posts: 15
- Joined: Thu Aug 18, 2005 10:12 pm
George, I'm not sure if you are actually planning a stop at the Trinidad Airport, but the airport in Raton, NM (RTN) is awesome and not much further from Trinidad, CO than the Trinidad Airport. The airport is in great shape and the folks at Pegasus Aviation will take great care of you (they live right on the field). Just my 2 cents.
PS. And the complimentary hot coffee and fresh baked cookies in the FBO sure hit the spot.
PS. And the complimentary hot coffee and fresh baked cookies in the FBO sure hit the spot.
Blue Skies!!
Brian Baker
Brian Baker
Trinidad is one of the original towns along the Santa Fe trail and is full of historic bldgs, museums, etc. I plan for Jamie and I to spend a day or so there in a B&B. Thanks for the recommendation! I'll look into the ground trans situation. (I suspect renting a car that remains in Colorado will be simpler than one across a state line. Besides...I'd hate to get cross-ways with the Mann Act.)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
TO MEENY MAN ACTS
YEW BETTER WORIE ABOUT NOT GITTIN CROCKSWAYS WITH THE WO - MANN ACT IN YER LIFE! I REKOMENN YEW STOP THAR AN GIT HER A FRESH COOKIE 
REMMER ITSA LOTS BETTER TO KEEP THEM WO-MANNS HAPPY THAN SUM DUM POLITISHUNS
REMMER ITSA LOTS BETTER TO KEEP THEM WO-MANNS HAPPY THAN SUM DUM POLITISHUNS
OLE GAR SEZ - 4 Boats, 4 Planes, 4 houses. I've got to quit collecting!
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jon s blocker
- Posts: 217
- Joined: Tue Apr 23, 2002 1:56 pm
mountain flying
We just got back from 4 days of mountain flying in New Mexico and Colorado. Being first timers we tried to follow recommendations from books and locals. The advise George has printed is excellent. We landed and took off in Angel Fire, NM, which is 8,500 ft., as the highest point we landed and took off from. If flying in the mountains, fly in the MORNING, this is the best air, and least turbulence. We have a '53 C170B, with a lyc 0-360, and a 80" constant speed. Our highest altitude we cruised at was 14,000 ft even. we spent considerable time at 11,500 to 12,500 ft. Rule of thumb is give yourself 2,000 ft above the highest area you will cross.I have a picture of one of our climb to altitudes, and we held a steady climb of 700 fpm at 78 mph and we were at 11,500 ft. Our mains were 3/4 full, but we didn't carry fuel in the aux tank in the mountains. The back seat was taken out, and the back was absolutely packed with camping gear, clothes, food, tools, coolers, chairs, you name it! If I can figure out how to post the picture, I will. The 170 with the extra power was a great flying plane that performed beautifully. Give yourself extra time to climb, density altitude is a huge consideration into where you can get to, and as George said, get to altitude BEFORE you get to your intended crossing point. Take off role is long, and landings are faster, so be prepared. Can't wait to go back. Taos was a hoot, got to get back there. Our fuel burn was between 8 1/2 - 9 gph. We had to lean to climb some, so take altitude into mixture consideration when climbing. We flew from Columbus, Ne., (visited the parents for a day), to Ingleside, Tx., ( OLU to T43) in 7hrs and 10 mins wheels up to wheels down! Max tail wind 10 knots 7,500 ft alt. With the aux tank in use again, we went from Columbus Ne. to Cleburne, Tx., non-stop, 4 hrs and 15 mins. Jon
Jon,
Sounds like you guys had a great trip! I'll bet your 180hp bird did just great. I'm headed up that way this weekend. Taking the new RV for it's first x-country up to Canon City, and will probably make a stop in at Leadville while we're there. I took a Taylorcraft up to Leadville 2 years ago. My first mountain flying experience and it sure was an eye opener.
Sounds like you guys had a great trip! I'll bet your 180hp bird did just great. I'm headed up that way this weekend. Taking the new RV for it's first x-country up to Canon City, and will probably make a stop in at Leadville while we're there. I took a Taylorcraft up to Leadville 2 years ago. My first mountain flying experience and it sure was an eye opener.
Craig Helm
Graham, TX (KRPH)
2000 RV-4
ex-owner 1956 Cessna 170B N3477D, now CF-DLR
Graham, TX (KRPH)
2000 RV-4
ex-owner 1956 Cessna 170B N3477D, now CF-DLR