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Alternate Filing With A WAAS Certified GPS

Since the advent of WAAS the rules and acceptable use of the panel mounted WAAS certified GPS has been constantly evolving. The panel mounted WAAS certified GPS allows us to file an IFR flight plan with an alternate airport with only a GPS approach, provided you comply with the defined requirements for filing an alternate.

First let us assume the weather at your destination is forecast to be 200 feet overcast and 2 miles visibility. Let us also assume our aircraft has a panel mounted TSO-145c WAAS certified GPS, no DME, and no ADF.

Per 91.169 the weather forecast requires an alternate because the ceiling is forecast to be less than 2000 feet. We look for an alternate and decide to use an airport with one GPS approach and the weather forecast of 1000 feet and 2 miles visibility.

Per AIM 1-1-20 the RNAV approach in our example is authorized as an alternate. We may file the airport with only a GPS approach as an alternate provided the weather minimums meet the non precision alternate minimums of not less than a ceiling of 800 feet and visibility of 2 miles.

Example 1 :

Lets plan an IFR flight from KORL to KLAL in an aircraft with a WAAS certified GPS, no ADF and no DME. The weather forecast for KLAL is ceiling 200 overcast with 1 mile visibility. We decide to use KTPF as our alternate because the weather forecast is 1000 overcast and 2 miles visibility. Since KTPF has a GPS approach and we have a WAAS GPS, we can use the alternate minimums off 800 foot ceiling and 2 miles visibility.

Example 2:

Instead of filing the alternate in Example 1 we decide to use KBOW as our alternate. Lets assume the weather at KBOW is forecast to be ceiling 800 and 2 miles visibility. This is one case where we can file KBOW only if we have a WAAS GPS since if you look at the alternate minimums only the GPS approaches have minimums defined and the VOR Approach is not authorized as an alternate.

Florida Alternate Minimums

Example 3:

Using the same flight as above we decide to use KGIF as our alternate. Weather at KGIF Is forecast ceiling 800 visibility 2 miles. Again we can use this as an alternate because we have a WAAS GPS.

If we did have a VOR and DME in the aircraft we could have used KGIF as an alternate if our GPS was inoperative, but since we don't have DME we can only file as an alternate based on the published GPS approaches.

Conclusion

A WAAS certified GPS has enabled us to get into airports we could never have been able to fly to in the past. Legacy navigation systems including non directional beacons were the only way to fly into small and remote airports for many years. With higher minimums than WAAS we were many times unable to get into our destination because of the low ceilings thus diminishing the utility of many airports. Only 10 years ago I remember having to divert on many occasions because I could not get into my home airport. With WAAS GPS I am able to make it in more often.

The WAAS GPS also gives us more options for filing alternates especially if the airplane we are flying has no DME either because the equipment is inoperative or removed from the aircraft. With that said we must remember to comply with the rules concerning filing alternates and we must also comply with additional requirements concerning RAIM, which is a topic of an upcoming article. Also remember if you do not have a WAAS GPS different rules apply for finding an alternate, which I will discuss in a future article.

If you have invested in a WAAS GPS you have increased the utility and safety of your aircraft. With WAAS you will be able to land at more airports and choose more airports as alternates.

This Article Sponsored by:

World Of Water - A PADI 5-Star dive center located in Tampa, Florida

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Bartow Air Museum

DSC_0049Flying allows us to see the beauty of the world from a unique vantage and affords many the opportunity to visit destinations both near and far. Today's
destination is Bartow Airport and the Aviation Museum. The museum was found
serendipitously when I stopped to pick up a friend at the Bartow airport. I wandered into
the brand new building to discover a treasure trove of pictures and artifacts from a time
when the airfield was used as a military training base.

History of The Bartow Army Airfield
DSC_0053In 1941 the mayor of Bartow acquired the land. Subsequently the land was taken over by the United States Government and developed as a training
base for the Army Air Corps. After the war, ownership of the airport passed back and
forth between the Government and the City of Bartow.

The United States government paid civilian contractors to provide initial flight training
and operate the airport for military training. The program was terminated in 1960 and
the airport was turned over to the city one final time. The airport now is a self supporting
through a mix of industrial park, fuel sales, and rent from tenants.

Museum Exhibits

Display cases throughout the museum and the terminal building offer a glimpse into not
only the importance of this aviation training base, but into the individual lives affected by
the base. Stories of the people who developed life long friendships are related through
pictures, printed stories, and video.

DSC_0024One such friendship ended in tragedy when two hometown buddies flying in separate airplanes collided with each other during a practice bombing
over Lake Hancock. Both where lost with and entombed in their P-51B aircraft at the
bottom of the lake. Years later aircraft parts where recovered and are now on display in
the museum. The exhibit is now a constant reminder of the dangers brought by war
both on the battle field and during training to become a soldier.

Lunch and a Rocking Chair

DSC_0067A great way to relax is to watch airplanes take off and land outside the window while eating breakfast or lunch at the Flight Line Grill. Adjacent to
the museum, the Terminal Grill offers comfort food at a reasonable price. After a meal step outside on the large patio and watch the planes fly in and out. Most days you will see a variety of aircraft flying at Bartow airport and you might even see a historic restored aircraft fly by.

Close to Disney and other Central Florida Attractions.

Located off I-4 between Orlando and Tampa you can make this a quick visit during your
vacation in Florida. For those flying into Bartow you can park in front of the terminal and
visit the museum only steps away.

For More Information:

Bartow Airport Museum Room

Fantasy Of Flight, Polk City, Florida:
An Aviation Attraction Where Dreams Of Flight Come True.

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Choosing The Correct Hold During The Approach.

One more approach and we were done for the day. We chose the RNAV 35 at Peter O. Knight Airport in Tampa, FL (KTPF) which takes us over the manatee viewing area over Apollo Beach.

My student reviewed the weather, loaded the approach into the GPS, and briefed the approach. All was going well until the controller issued the clearance "cleared direct HUMKI, maintain three thousand, cleared for the RNAV 35 approach".

The flight plan page was selected, HUMKI highlighted and the direct-to button was pressed. NAV was selected on the autopilot and we were on our way towards HUMKI for one turn in the hold which should position us for the inbound course, or that is what we though we where doing.

It was a typical fall morning in Tampa Bay, smooth cool air without a bump the entire flight. Relaxed and enjoying the wonderful views I thought to myself, boy this is going to be a great end to the day until I noticed something odd, two magenta letters MH next to HUMKI on my GPS.

"Why does it show we are holding at the missed approach point when we are just starting the approach?" I said with a perplexed tone. My student looked up at me from under his view limiting device with an even more confused expression indicating both of us did not realized what had happened.

It suddenly dawned on us that we had selected HUMKI on the flight plan but the wrong HUMKI. HUMKI is displayed twice, once as an initial approach fix and then as the holding point for the missed approach. We had selected the later and were navigating towards our missed approach point.

We quickly reactivated the approach and then began flying direct-to HUMKI for one turn in the hold to realigning ourselves for the inbound course. To my delight a magenta IA was after the waypoint HUMKI and the word hold was displayed in the flight plan. Proceeding towards the initial approach fix opposed to the missed approach holding point defined by HUMKI I began to reflect on what went wrong and why.

Lessons Learned

When preparing for the approach either activate the approach or proceed direct-to a fix on the approach. Using the direct-to a fix on the approach will automatically activate the approach in the G430W.

Before pressing the direct button it is good idea to take a moment and verify you have selected the correct point along the approach. This is especially important when the fix defines multiple points along the approach. In our case HUMKI is the Intermediate Fix, Final Approach Fix, And the Missed Approach Holding Fix.

As is true with most buttons in the aircraft it is best to take your time when selecting and pressing any switch or button on the GPS. Next time you hit direct-to make sure you look at the fix and verify that you have entered it properly. Most airline operating procedures require both pilots to verify any fix prior to entering it into the navigation equipment. Maybe we should adopt this methodology in the aircraft we fly. Verbally say to yourself "selected" and "verified" each time you make a change to your navigation system and you will have less entry errors while flying.


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Bird Strikes Hazards and Avoidance

Due to the recent accident of a US Airways jet landing in the Hudson River caused by a possible bird strike, I have decided to publish my presentation on Bird Strikes Hazards and Avoidance. You will need powerpoint to view the presentation.

http://www.expertaviator.com/images/BirdStrikesHazardsandAvoidance.ppt


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GIFT of Flight: An After Takeoff Checklist

A morning flight is truly a treat. The air is smooth and the the sun presents a spectacular natural light show, transitioning from an amber glow to a yellow beam of light. An anticipatory smile grew on my face as I woke one fall morning, expecting an exciting day of flying ahead.

This seemed a perfect morning for a flight lesson, with a clear blue sky above and calm winds. My student John is a quick study, and I was expecting to complete training for his complex endorsement on this day.

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Know Your Radar: Is that a thunderstorm ahead?

Flying towards Houston on a clear night, I sat reclined in my seat, watching the brilliant and sparkling cities slipping slowly under the aircraft. As I gazed through the front window, the area ahead appeared to me as a large black hole devoid of the familiar small dots, signifying civilization ahead . It was at this moment I remembered I should turn on the Radar to see what might be in the dark abyss ahead.

I was confident there would be no significant weather on our route of flight except for some light rain showers. Waiting for the radar to begin displaying, I turned to the mechanic in the jump seat. Enjoying the great weather along our route, we both agreed we disliked flying near or through thunderstorms.

I noticed a look of worry in his face as he lifted his hand and motioned towards the instrument panel. He seemed to turn slightly pale when he announced, "this doesn't look good". As the radar came to life a large round red blob displayed 100 miles ahead and over our destination. I could feel my heart rate increase. Did I not read the weather forecast properly?

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Professionals and Professionalism

I was enjoying my favorite form of relaxation, reclining at a small airport, viewing the sun setting in a grand showcase of blue sky and soft orange glow reflecting off wispy clouds. I lean against the chain link fence and watch the planes take their position on the runway. The pilots bring the power up to full throttle and the planes move slowly at first, gaining speed gradually. Within short order the airplane's nose is pointed towards the sky, as if asking the wind to assist the human engineered bird to fly. Slowly the plane separates from the ground and becomes a part of the sky above. I envision myself in the cockpit, enjoying the feeling of escaping the grasp of earth's gravity.

Watching planes during this lazy summer day, I notice a friend approaching me with one of his student pilots. His wide grin I interpreted as his shared joy in being at an airport. He gave me a friendly hello and strong handshake. Turning to his student he introduced me as a professional pilot flying for the airlines.

My friend and I agreed as to the beauty of the day, all the while relating how blessed we are in being able to enjoying the wonders of flight. After discussing different landing techniques, my friend and his student returned to their aircraft to finish their discussion. I began pondering my friends description of me as a professional, all the while hoping he further considered himself a professional. I then considered the question, "what is a professional?"


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Slouched over my coffee, the morning fog in my mind had not lifted, I held the warm cup in both hands helping extract the heat. Raising my eyes, slowly focusing on the television, a 747 jumbo lumbering into the sky came into focus. As always, a plane on television was a greater boost to my state of awareness than the caffeine in my coffee.

Luckily, I caught the beginning of an episode from The History Channel’s Our Generation titled “Fly With Me”. This is one part in the The History Channel’s Our Generation series, depicting life changing events of the baby boomer generation.

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Saving historic centers of commerce and recreation.

As a child the sound of an airplane made me stop and look skyward wondering how the plane can stay aloft without flapping its wings. As an adult I find myself looking at the passing planes but with more insight into the physics involved in keeping these sleek machines aloft. Growing up in Basking Ridge, New Jersey I would ride my bicycle to Somerset Hills Airport and watch the wonders of flight take place before my youthful eyes. Mesmerized by the planes taking off and landing I would pretend I was the pilot at the controls and make airplane sounds while watching. The planes departures and arrivals reminded me of the Canadian Geese I would watch while walking through the Great Swamp located next to the airport. Most days I would daydream and wonder what direction the planes where traveling and what new discoveries they would find flying to their destination. Unfortunately, the airport was demolished and condominiums grew from the paved runway which once housed small aircraft of all shapes and colors. My childish mind assumed the planes moved on to other airports similar to birds finding a new nest when their old habitat is destroyed by a predator.

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If you are like me and enjoy hanging around small airports you tend to see the same familiar faces. Many enjoy visiting the airport for some "hanger flying" , while others use any excuse to jump in a plane and fly somewhere for the "hundred dollar hamburger". One day I noticed that a friend of mine was missing from the normal airport crowd.I had become friends with a student who had been flying with me. We spent many hours flying and discovering new places to visit while fulfilling his obligation to the insurance company of a minimum 25 hours in the aircraft before flying solo in his new plane.

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