Date: 201810
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Light: Daylight
Aircraft: B737-800
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Flight phase: Takeoff / Launch
Aircraft component: Air Data Computer
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Human factors: Confusion
Second reporter function: Pilot Flying; First Officer
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Rejected Takeoff; Flight Crew Returned To Gate; General Flight Cancelled / Delayed; General Maintenance Action
Contributing factors: Aircraft; Human Factors
Primary problem: Aircraft

Narrative: We departed on time and proceeded to the runway without issue and were cleared for takeoff. As we neared 80 knots; the First Officer said 'I've got no data.' It took me a moment to comprehend what he said and I looked across to his flight instrument display. There was no airspeed or altitude data. The numbers and gray stripes were gone and only the HSI and Compass displays were showing. It took me a moment to process the situation and I elected to abort the takeoff. As I did so; I looked at my airspeed indicator and saw that we were slightly past 100 KIAS. I had never made the '80 knots' callout since the FO (First Officer) pre-empted that with his statement. I deployed the thrust reversers and RTO (Rejected Take-Off) worked as expected to bring us to a stop.The FO informed the Tower of the abort before we stopped; and I made a brief PA to the cabin after we stopped. Unfortunately at that point I reverted to our old QRH and called for the RTO Checklist. It didn't take us long to realize that that was a mistake and we then started talking about brake energy. The Tower asked if we could clear the runway and asked if we needed to go the hot brake area. We told them we could move and needed to evaluate the brakes. As we taxied clear; the FO went into the FMC to get the data. He made multiple attempts and we got error messages every time.After clearing; we contacted [Operations] to tell them we needed to return to the gate. I taxied slowly towards the gate as we continued to try to get some brake cooling data. We changed all the entries that we thought reasonable; but nothing worked. Later in the day we reviewed the [data] module from the [Operational Manual] and I am convinced we made the correct entries. At that point I decided to return to the gate. Based on my experience I didn't believe that the brake energy would require remote parking. In hindsight I should have gone somewhere remote and worked with Dispatch to get the brake cooling data.Later; after we got a different aircraft; we tried running the brake cooling data again. The module in the FMC was confusing. If we selected 'Takeoff;' the braking options were the landing options for autobrakes; and if we selected 'Landing'; the only braking option was RTO. We could not get any data out of it. We then tried using the app on the iPad. If the normal departure point [was entered] we got the same error messages that we got after the RTO. If the full length of runway was entered; we finally got brake energy data. It appeared to me that there is some kind of glitch or problem getting brake energy data [for takeoff from that intersection].


Second narrative: This was day two of a three-day trip. The Captain and I had flown two legs together the first day. We were in ZZZ cleared for takeoff on Runway XX/A; and at 80 knots I noticed that I had no speed or altitude tape on my outboard [display]. I made it known and the Captain elected to abort the takeoff. Once we were clear of the runway the Captain requested that I run the brake cooling numbers from [Performance Calculator]. I entered the information into [Performance Calculator] and got a message back saying something to the tune of 'Please enter a proper runway for which you departed from that was also in [Performance Calculator]'. I went back and looked at the data in [Performance Calculator] takeoff to make sure I had entered it properly and then went back to brake cooling; and ensured I had entered all the information there properly. I did this a number of times and still was not able to get any brake cooling numbers. This was my first time using the brake cooling software on the line since training; so I thought I might be doing something wrong. The Captain and I were getting very frustrated by the inability to get the right information and instead of following the guidance in the QRH to park remotely and contact Dispatch for numbers; we decided to go to the gate. I was all wrapped up in trying to get the numbers to work that I failed to trap the error of going back to the gate without contacting Dispatch. After we got back to the gate; and had a little time before we could get another aircraft; the Captain and I went through the [Performance Calculator] reference guide and made sure that we were doing everything correctly. There was nothing that stood out to us that we were doing wrong with inputting the information. Once we finally left on another aircraft I tried running the brake cooling numbers for the new flight off of Runway XX/A. Again I got the same error message; and then tried it again; and instead of within the software having a Takeoff drop-down with RTO (Rejected Take-Off) selection; it was flip flopped to Takeoff with A1; A2; A-max... and landing with RTO. There seemed to be an error with the brake cooling software. It could have been that we had already taken off so there is some logic built into weight on wheels sensors.Any rate to sum this up I finally got out my iPad app and ran the numbers on it. Same issue happened when I ran runway XX/A. I then changed the takeoff runway to XX full and XYL full and it worked. I also ran XYL/B and I got the same error message. I think there might be a coding issue with brake cooling for intersection runways.In the future I will try to trap the errors that happened this time due to this experience. The real reason for this [report] is to bring to light the issues we had with brake cooling data; but I also recognize that there was the error of not contacting Dispatch to get them involved. I am not sure if they would have been able to get good data for XX/A; but it would have been helpful to have someone else in on the conversation that hadn't just dealt with a rejected takeoff.


Synopsis: B737-800 flight crew reported rejecting a takeoff after the First Officer lost PFD data; then being unable to get brake cooling data afterwards.