“You’re headed to your high school reunion in The Dalles, Oregon (DLS), this Friday for festivities that start at 5:30 p.m., and you’ll use your Beechcraft Bonanza for the trip. A high school friend and her husband will come with you but can’t get out to the local airport in Coeur d’Alene, Idaho (COE), until 2 p.m. PDT. The three of you plus baggage weigh 690 pounds so full fuel may not be an option. Use the forecast weather for the day to plan a flight and be prepared to file IFR. Arriving at the airport, you find a 200-foot overcast ceiling with no signs of lifting before takeoff.”
Each candidate who takes a practical exam for the instrument rating arrives with preparations for a cross-country flight using a scenario like this one. Even if the departure and destination airports predict visual meteorological conditions, we assume ceiling and visibilities necessitate instrument procedures throughout the flight. While departing in low conditions might run against personal minimums, such operations are legal in Part 91, so we complete the thought exercise, nevertheless.
A recent instrument rating candidate, Kevin, showed me his flight plan: KCOE KARPS V120 GEG V444 ALW VECCU followed by the LDA DME RWY 25 into KDLS. Kevin planned to file for 8,000 feet msl and take advantage of the 16-knot winds from the northeast that would reduce flying time.
I administer most practical exams in Tennessee, and it occurred to me years ago that one can earn an instrument rating by exclusively flying around the flat terrain in the southeast. But the earned privileges allow a pilot to file and conduct an IFR flight through the mountainous terrain out West and he may find out the hard way that his preparation was lacking. Kevin noticed that the approaches into Columbia Gorge Regional/The Dalles Municipal Airport offer minimums that are higher than most VFR traffic patterns, and he was intrigued by the LDA approach with which he was unfamiliar. He did his homework and was ready to discuss what would be an interesting culmination to the flight.
But my first question during the practical exam revealed a troubling lack of preparation. I explained that he was “cleared as filed” and was given a clearance void time for departing Runway 24. I then asked Kevin to detail how, from takeoff to touchdown, his plan guaranteed adequate terrain and obstacle clearance. He explained that, while his filed altitude of 8,000 feet fell below the minimum enroute altitude (MEA) on V120, he would be navigating using his GPS so staying above the 7,600-foot minimum obstruction clearance altitude (MOCA) would suffice. After that, he would be well above any other MEAs and the approach into The Dalles would provide that safety. I pressed further by asking how he would avoid obstacles between takeoff elevation of 2,320 feet msl to 7,600 feet msl on V120. Kevin stared blankly, shrugged, and said he’s sure that ATC would vector him in a direction that would keep him and his passengers safe. That would be nice except that’s just not the way it works. In fact, ATC may not even be able to pick him up on radar until he’s several thousand feet above the ground. And I reminded him that the IFR system is set up so that, during a loss of communication event, the pilot can complete the flight successfully.
The question that stumped Kevin sounds simple but is the one I find most problematic on instrument (and even flight instructor instrument) practical exams. In fact, it’s the topic that appears most often in a notice of disapproval I issue based on the conversation on the ground.ATC may not even be able to pick you up on radar until you're several thousand feet above the ground.
During the debrief, I asked Kevin to pull up the Coeur d’Alene airport in his electronic flight bag and search for any departure procedures. Standard instrument departure procedures (SIDs) are typically associated with busy airports and can effectively reduce pilot and ATC communications and workload while guaranteeing obstacle clearance. Airports like Coeur d’Alene don’t have SIDs but still have a plan, an obstacle departure procedure (ODP), to guarantee obstacle and terrain clearance from takeoff to the enroute phase of the flight.
The Coeur d’Alene 2 ODP is published in graphical form (above) and requires, after departing Runway 24, turning left to join the 232-degree radial from the COE VOR. Upon reaching 5,300 feet msl, turn right back to the COE VOR and then fly along the 107-degree radial from COE to KARPS and then on course. Assuming the aircraft can achieve the standard climb gradient of 200 feet per nautical mile, the circuitous route provides safety from takeoff to flight along V120.
I reminded Kevin that whether we are assigned a SID, choose an ODP, or arrange our own plan (with care, please!), it’s our responsibility as pilots to ensure that the plans we file are safe and that we brief them thoroughly before departure.
And departure procedures aren’t just for instrument-rated pilots. If you’re departing an unfamiliar airport with obstacles or higher terrain, check to see what departure procedures are available in your EFB. Flying a SID or ODP can ensure a safe way to depart under visual meteorological conditions too.
When using departure procedures, it makes sense to remember two items. First, your airplane must be able to achieve the climb gradient specified on the chart and that’s based on groundspeed. For example, if an aircraft climbing at 100 KTAS with a 20-knot tailwind needs to maintain a 450 feet per nautical mile climb gradient then the necessary climb gradient is GS*CG/60 = 120*450/60=900 feet/min. While that might seem doable, a normally aspirated aircraft might struggle to achieve that when density altitude is high.
Second, some departure procedures involve circuitous routes or extended climbs in a holding pattern until reaching the MEA. At least have a way to ballpark the extra time and fuel you’ll need to add and update your navlog accordingly.
When planning your next cross-country adventure, whether filing IFR or enjoying the gorgeous terrain our country offers, a departure procedure might be just what you need to get the trip started off right.
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